Phase 1, Engineering Validation

A Proposal for YogaTree

YogaTree: Magnetic Stabilization System

6 Weeks

USD 6,500

Final Proposal

01 — Background

Background

YogaTree LLC is a United States product company founded by Theresa Marqua, based in Santa Monica, California. Theresa has practised yoga for 20 years, much of it hot yoga, and has built the product around a problem she has lived with throughout that time.

In a heated room, a yoga towel bunches, creases and slides across the mat. The existing answers on the market are silicone dot backings, which still move once the towel is wet, and corner snap fasteners, which sit proud of the surface and are awkward in use. Theresa's solution is a concealed rare earth magnetic attachment system that holds the towel to the mat at the corners, stays completely hidden, and releases cleanly for laundering.

There are three products in the launch line covered by this proposal:

YogaTree Premium Yoga Mat. 72 in x 24 in, natural rubber base with a high-grip polyurethane surface, matte black, laser-engraved branding.
YogaTree Hot Yoga Towel. 72 in x 24 in, premium microfibre, black, printed metallic gold branding, machine washable.
YogaTree Magnetic Face Towel. A small companion microfibre towel with a single concealed magnet at one corner that attaches to the mat.

The product is protected by a filed United States provisional patent application, and a mutual non-disclosure agreement is in place between YogaTree and C2W Group.

Theresa has produced a clear and well-considered product specification setting out design intent, materials, magnet placement, branding and performance requirements. That is a strong and unusually complete starting point at this stage. What does not yet exist is the engineering: there is no manufacturable CAD, no 2D drawings with tolerances, and no validated bill of materials. That is entirely normal for a product at this point in its life, and it defines the work in front of us.

C2W and Shield Works have been asked to take YogaTree from specification to a proven, manufacturable premium retail product. This proposal covers Phase 1 of that program, titled Engineering Validation, following the discovery call held on 24 July 2026.

02 — Our Preliminary Read

Our Preliminary Read on the Product

Ahead of any paid engagement, our engineering team has reviewed the tech pack, the intake form, the discovery call notes and the supporting drawings. The following is not the Phase 1 output. It is the position our work will start from, and it is set out here so that the basis of the fee is visible before Theresa commits to anything.

2.1 The attachment architecture is not yet settled

This is the most important observation in our review, and it is a positive one, because it is precisely the question Phase 1 exists to close.

The YogaTree documentation contains three different candidate architectures for the corner attachment:

Magnet to magnet, using discs embedded directly into the mat and into the towel, with matched polarity.
Magnet to magnet, using magnets fully encapsulated inside moulded polymer pods that are set into the mat and sewn into the towel corners.
Magnet to steel, using a flush magnet on the visible face and a stainless steel snap stud on the underside.

All three are viable engineering routes. They are not interchangeable. They differ materially in unit cost, tooling requirement, wash durability, surface feel, assembly method, and in how the product behaves in the hand. Supporting dimensions also vary across the documents, including mat thickness, face towel size, magnet diameter and magnet grade.

None of this is a problem with the concept. It is the normal gap between a well-argued product idea and a controlled engineering specification. Selecting one architecture, proving it, and reconciling the specification into a single controlled document is the first substantive job of Phase 1, and it is the point at which YogaTree stops being three possible products and becomes one manufacturable one.

2.2 Where quality, cost and timeline are actually won or lost

Magnet grade against operating temperature.

Neodymium magnets trade strength against heat tolerance. The highest grades are the strongest and the least heat tolerant. Higher temperature grades hold their performance in heat but pull less hard. A heated studio and a domestic wash and dry cycle together set the operating envelope, and the right grade sits where those two requirements meet. This is resolved through engineering assessment in Phase 1 and confirmed by physical testing at prototype stage in Phase 2, rather than by specification alone.

Integration into natural rubber.

Natural rubber is cured at temperatures that sit above the safe operating limit of most neodymium grades, so a magnet moulded in during cure cannot be assumed to survive the process with its performance intact. The likely routes are post-insertion into a moulded recess, or a protective carrier pod set into the mat. Establishing which is correct, and at what cost, is core Phase 1 work.

Integration into laundered microfibre.

A rigid disc sewn into a soft textile that is washed repeatedly behaves very differently from the same disc set in rubber. Seam fatigue, movement of the magnet inside its pocket, and the feel of the corner against the hand and foot all follow from the encapsulation and retention method chosen.

Corrosion and sealing.

Neodymium corrodes readily. Sweat is saline and detergent is alkaline, so the sealing system faces both. Plating specification and full encapsulation both matter, and the seal is confirmed by a defined test protocol rather than assumed from the material datasheet.

Orientation and polarity.

In a magnet to magnet design, matched polarity means the towel attaches in one orientation and repels in the reverse. A magnet to steel design is indifferent to which way round the towel is laid. This is a genuine usability decision that shapes how the product feels to a customer in a studio, and it is one of the clearest arguments for settling the architecture before anything is tooled.

Surface concealment and cosmetics.

Holding a rigid inclusion flush and invisible beneath the surface of a flexible mat that is rolled and unrolled every day is a cosmetic engineering problem as much as a structural one. Surface telegraphing over the magnet and edge lift around the pod are the known failure modes in this type of construction, and they are addressed through recess geometry, pod profile and lamination.

2.3 Design maturity note

The commercial intent behind YogaTree is clear, the market positioning is well argued, and the specification is more complete than most products we see at this stage. The gap is engineering, and it is a well-defined gap rather than an open-ended one. There are no electronics, no power, and no software in this product. There is one hard technical question, applied across three substrates. That is a focused piece of work with a clear finish line, which is why Phase 1 for YogaTree is scoped tightly rather than broadly.

03 — Volume & Timeline

Volume and Timeline Targets

The following reflects current working assumptions drawn from the tech pack, the intake form and the discovery call. These will be reconciled and validated through Phase 1.

Initial Production Run	Approximately 100 to 200 mats and towels (client indicated)
Second Production Run	Approximately 500 mats and 500 towels (client indicated)
Annual Forecast	Approximately 3,000 units (client indicated)
Quantity Breaks to be Costed	100, 250, 500, 1,000 and 3,000 units
Target Unit Cost	To be established through the Phase 1 Indicative Quotation
Target Retail Price	USD 300 for the set, USD 225 mat, USD 125 towel (client indicated)
Target Markets	United States primary. Premium retail and studio channels
Production Timeline	Set against the Development Roadmap on completion of Phase 1

04 — Phase 1

Phase 1, Engineering Validation

Phase 1, Engineering Validation is the first paid engagement in the YogaTree development program. The work is engineering-led: reconciliation of the specification into a single controlled design basis, a dedicated engineering workstream on the magnetic attachment system across all three substrates, a DFM, DFA and DFX assessment across the mat and the soft goods, supplier engineering engagement with indicative pricing at quantity breaks, and a Development Roadmap that consolidates the output into a costed phase-by-phase pathway to qualified mass production.

Duration: Phase 1 begins on receipt of payment and completion of the Engineering Kick-off Workshop. Estimated completion is 6 working weeks from receipt of the required physical samples at Shield Works, Zhuhai, provided those samples arrive within the first two weeks of the engagement.

Phase 1 consists of the following six deliverables.

Engineering Kick-off Workshop

A working technical session with Sourya Ghosh, Head of R&D, and the Shield Works R&D team. This is not an introductory call. We work through the product line, the three candidate attachment architectures, the branding and cosmetic requirements, Theresa's retail positioning and cost targets, and the laundering and heated studio conditions the product has to survive. Engineering priorities and workstreams are agreed before work begins. Theresa has direct access to our engineers from this point.

Design Feasibility Assessment and Specification Reconciliation

A written, annotated engineering assessment of the YogaTree concept, consolidating the existing documentation into one controlled specification. This resolves the conflicting dimensions, magnet sizes and grades, and construction methods carried across the current pack, and confirms a single agreed design basis for the mat, the hot yoga towel and the face towel. Where the existing concept is sound, we will say so and leave it alone. Output includes a structured bill of materials and a ranked list of recommended design directions for manufacture and cost.

Magnetic Attachment System Engineering Workstream

The dedicated engineering workstream on the central technical question, and the largest single element of Phase 1. This covers selection between the magnet to magnet and magnet to steel architectures against strength, orientation behaviour, cost and durability; magnet grade direction against the operating temperature envelope; the encapsulation, sealing and corrosion protection strategy; the retention and anti-rotation method in both rubber and microfibre; target attachment force set for secure hold and comfortable one-hand release; and the integration method into natural rubber given its cure temperature. This deliverable also defines the physical test protocol for wash cycling, sweat and salt exposure, elevated temperature, attachment force and retention over life. Testing is executed during the Phase 2 prototype and validation stage using the necessary supplier or third-party facilities, coordinated and interpreted by Shield Works. Output is a documented engineering position with trade-off analysis and a recommended direction.

Preliminary DFM, DFA and DFX Engineering Assessment

Written assessment covering design for manufacture and assembly across the mat, the towels and the magnetic sub-assembly, tooling strategy and indicative tooling direction, surface finish and branding execution including laser engraving and print, structural packaging direction, assembly sequence, and a structured risk register with mitigations. This deliverable also includes a review of preliminary United States labelling, consumer warning and material compliance considerations, including magnet related warnings, natural rubber latex disclosure, and whether any California Proposition 65 assessment is required. This review is directional and is intended to identify what needs formal attention, not to replace it. Preliminary at this stage against analysis and supplier data. Full DFM execution, drawing release and supplier qualification testing sit in Phase 2.

Supplier Engineering Shortlist and Indicative Quotation

A qualified supplier shortlist drawn from the Shield Works supply chain and wider network, with first-round engineering engagement to confirm capability and capacity across rubber moulding, microfibre textile manufacture, magnet supply and encapsulation, and finishing and print. Indicative unit pricing at the quantity breaks set out in Section 3, benchmarked across the shortlisted suppliers. Accuracy is subject to the defined level of readiness for manufacture. Final unit costs are locked against specific supplier quotes as Phase 2 progresses.

Development Roadmap (Full RTMP)

The consolidating document that carries the Phase 1 engineering output forward into Phase 2 and through to qualified mass production. This is the full Route to Market Plan for YogaTree, and it is the document Theresa builds her funding and launch plan against.

The Development Roadmap will include:

Phase timelines and phase management costs across the full development program.
Shield Works resource allocations and deliverables across sampling, development, design optimisation, prototyping, pilot run manufacture and mass production.
Consolidated written output of the Phase 1 engineering work, including the reconciled specification and the magnetic system workstream.
Component-level bill of materials with material specifications and qualified supplier direction.
Tooling strategy and indicative tooling investment direction.
Prototyping and iteration plan with defined validation gates, including the physical test protocol defined in Deliverable 3.
Pilot run manufacture plan with quality control gating criteria.
Mass production pathway and scaled production goals.
Packaging direction and indicative packaging cost.
Risk register with mitigations and owner assignments.

Note: Phase 1 is the first phase of the YogaTree development program. Phase 2 and all subsequent development, tooling and production work is scoped and costed within the Development Roadmap for Theresa's approval before any execution begins. No tooling commitment is made until the prototype and validation stage confirms manufacturability and cost alignment.

Fee: USD 6,500, payable in full on project confirmation.

05 — Exclusions

Exclusions

The Phase 1 fee covers all six deliverables in Section 4 in full, including the engineering work, the specification reconciliation, the magnetic system workstream, the DFX assessment, supplier engagement, the indicative quotation and the Development Roadmap. The following are excluded and are scoped and costed within the Development Roadmap itself.

The YogaTree magnetic copper water bottle. This sits outside the scope of this proposal. It is a different material set with a different supply chain and its own food contact compliance requirements. We are happy to assess and quote it separately at any point.
Full DFM execution, engineering drawing release and supplier qualification testing.
Prototyping, sampling and physical testing, including execution of the test protocol defined in Deliverable 3.
Tooling and mould costs.
Shipping of samples or prototypes between the United States and China.
The manufacture or purchase of production units. Indicative unit pricing is included under Deliverable 5.
Patent filing or prosecution fees. Guidance is included where relevant. Filing costs are separate.
Accredited third-party product testing and certification fees, coordinated through external partners and quoted separately if required.
Brand and packaging graphic artwork. Structural packaging direction is included. Graphic artwork remains with YogaTree.

Note on the model after Phase 1: once a supplier set is confirmed and production begins, C2W and Shield Works act as YogaTree's manufacturing partner. Theresa receives a single unit cost for each item that covers goods, assembly, quality control, supplier management, packaging and logistics coordination. These are not billed as separate service fees. The Phase 1 Supplier Engineering Shortlist and Indicative Quotation is designed to establish those unit costs with confidence before any production commitment is made.

06 — Payment Terms

Payment Terms

Engagement Fee

USD 6,500

payable in full on project confirmation

Stage	Fee	Payment Trigger
Phase 1, Engineering Validation	USD 6,500	Payable in full on project confirmation

Payment can be made by credit card, ACH or international bank transfer.

The scope and fee set out in this proposal remain valid for 30 days from the date above. The engagement becomes binding on written acceptance and payment of the Phase 1 invoice.

07 — Safeguards

Safeguards and Clarifications

Magnetic performance.

Phase 1 establishes the recommended magnet architecture, grade direction, target attachment force and validation requirements through engineering assessment and supplier data. Final temperature resistance, holding force, corrosion resistance and wash cycle durability are confirmed physically during Phase 2 using prototype assemblies and appropriate supplier or third-party test facilities.

Physical samples.

Phase 1 is materially better with physical samples in front of our engineers. What is useful is the existing mat and towel constructions referenced in the specification, together with any magnetic mock-ups Theresa has made and any competitor products she considers relevant. These do not need to be production-ready YogaTree prototypes, and nothing needs to be manufactured specially. Whatever exists today is what we want to see, because it lets our engineers assess how the current construction actually behaves rather than working from documentation alone.

Specification reconciliation.

Phase 1 delivers one agreed, controlled specification. Where the current documentation carries alternative constructions or dimensions, our engineering recommendation is presented with the reasoning, and the final selection is made with Theresa before it is carried into the Development Roadmap.

Compliance review.

The United States labelling and compliance review inside Deliverable 4 is preliminary and directional. It identifies what needs formal attention and the likely pathway. It is not a certification, a test report, or legal advice. Accredited testing and certification are coordinated through specialist partners and quoted separately.

Quotation accuracy.

The Phase 1 Indicative Quotation is based on the reconciled design direction, supplier engagement and the available level of manufacturing definition. It provides a credible planning range at the stated quantity breaks. Final production pricing is confirmed during Phase 2 against the completed engineering package, physical prototype, approved materials and specific supplier quotations.

Intellectual property.

YogaTree retains all intellectual property in the product, including the design, the CAD, the bill of materials and any derivative work produced under our engagement, on full payment for the work. Shield Works operates within an IP-secure, ISO-certified facility. Appropriate confidentiality agreements are put in place with third-party suppliers before confidential product information is disclosed. Supplier engagement is managed through Shield Works under our ISO supplier management and IP control procedures.

Product responsibility.

YogaTree, as brand owner, retains ultimate responsibility for the finished product's market placement, consumer warnings and regulatory compliance. Shield Works is responsible for carrying out the agreed engineering and manufacturing work professionally, manufacturing to the approved specification, and identifying areas that require specialist testing, certification or legal review. Where something needs formal attention, we will always tell Theresa plainly.

Timelines.

Phase 1 begins on receipt of payment and completion of the Engineering Kick-off Workshop, so the specification reconciliation, supplier research and initial architecture assessment start immediately and do not wait on shipping. The 6 working week completion estimate runs from receipt of the physical samples at Shield Works, Zhuhai, on the basis that they arrive within the first two weeks. Shipping and any customs clearance sit outside the estimate. The estimate assumes reasonable availability for the kick-off and follow-up technical discussions.

Scope changes.

If requirements change materially during Phase 1, for example the addition of further products to the line or a change in target volumes or certification requirements, we will adjust cost and timeline accordingly and agree any change with Theresa before proceeding.

08 — Why C2W & Shield Works

Why C2W and Shield Works

British-owned and managed, established in 2005 and marking 21 years in 2026. Over 20,000 completed projects, a team of 150 and more, and a network of 550 and more approved suppliers across Asia.

In-house R&D, mechanical engineering, DFM and DFX, quality control and audit resources, led by Mark Jacobs, a mechanical engineer with over 27 years of manufacturing experience and CEO of Shield Works and the C2W Group, alongside Sourya Ghosh, Head of R&D, who has an aerospace engineering background and leads the engineering content of every Phase 1 engagement.

Direct experience with rare earth magnet integration in consumer products, and with multi-material assemblies combining moulded components and soft goods.

Our own IP-secure, ISO-certified manufacturing facility, Shield Works in Zhuhai, for assembly, quality control, packaging and warehousing, with rubber moulding, textile manufacture and finishing delivered through our qualified supply chain as part of a single all-in unit cost.

A full-time dedicated project manager in our China HQ coordinating every supplier and engineering resource, so Theresa has full visibility of who is making what and where.

One commercial counterparty for the whole supply. No hidden middlemen, no opaque quotes, and no surprises on quality.

09 — Next Steps

Next Steps

Theresa confirms acceptance of this proposal and the Phase 1 fee.

C2W issues an invoice for USD 6,500.

On receipt of payment, we hold the Engineering Kick-off Workshop with Sourya Ghosh and the Shield Works R&D team. Phase 1 begins at this point, so the specification reconciliation and supplier work start straight away.

Theresa sends the available YogaTree samples, magnetic mock-ups and any relevant competitor products to the Shield Works R&D team in Zhuhai, ideally within the first two weeks.

The full Phase 1 output, including the Development Roadmap with costs and timelines at quantity breaks, is delivered approximately 6 working weeks from receipt of those samples, and potentially sooner where everything runs smoothly.

This proposal is intended to give Theresa complete clarity on cost, structure and exactly what Phase 1 will produce before any commitment is made. If the direction is right, we can move to confirmation at her convenience and get started.

Best regards,

Mark Jacobs

CEO, C2W Group / Shield Works

July 2026