Shield Works — Phase 1, Engineering Validation for Flow Engineering

01 — Background

Flow Engineering & the CR1 Engineering Validation Engagement

Flow Engineering is a Hong Kong based product venture founded by Vinesh Patel. The CR1 is the first product from the venture: a high-throughput consumer air purifier built around standard 16 by 25 by 1 inch pleated particulate filters, with deliberate non-connected, no-app, no-WiFi positioning. The product is engineered to combine genuine particulate performance with a premium aesthetic, addressing a category currently dominated by either expensive connected appliances or visually compromised Corsi-Rosenthal style builds.

The product architecture is a lightweight aluminium 3030 extrusion frame with 1 mm powder coated 5052 aluminium panels, five 120 mm axial PWM fans on a daisy chain, and a Class II external 12 V DC power supply (Mean Well NGE30I12-P1J). Fan control is via a simple analog PWM PCB with a tactile on/off switch and a 10 to 98 per cent duty cycle range. The PSU is supported across US, EU, UK, AU, CN, KR, and IN plug variants, allowing a single unit platform across all target markets.

Vinesh has built a working functional prototype with approximately USD 150 of materials. CAD (STEP), 2D drawings, bill of material, PCB gerbers, and schematics are available for sharing with the Shield Works R&D team ahead of the Engineering Kickoff Workshop.

The commercial route to market is a crowdfunding launch via Indiegogo or Kickstarter. The launch acts as the commercial validation gate: a successful campaign hitting 500 units unlocks the first production run and the full program into qualified mass production. Target retail is USD 249 to 299. Initial markets are the US, UK, and EU, with the PSU plug variants supporting secondary market expansion.

C2W Group and Shield Works have been engaged to assess the current design independently, provide an expert manufacturing and engineering perspective across the mechanical and electronic architecture, and map the pathway from the current prototype stage through to qualified mass production. This proposal covers Phase 1 of that program, titled Engineering Validation, following the discovery call with the C2W team.

02 — Volume & Timeline Targets

Program Targets

The following reflects current working assumptions drawn from the provided brief, the abridged spec sheet, and the discovery call notes. Final pilot and production figures will be reconciled and validated through Phase 1.

Item	Current working assumption
Engineering Prototype Quantity	5 final prototypes for crowdfunding marketing samples
First Production Run	500 units, contingent on successful crowdfunding launch
Annual Volume Forecast	To be confirmed in the Development Roadmap
Target Retail Price	USD 249–299
Target Markets	US, UK, EU primary. AU, CN, KR, IN secondary via PSU plug variants
Target Start	Ready to proceed on proposal confirmation
Funding Status	Personal capital, secured

03 — Phase 1, Engineering Validation

Six Phase 1 Deliverables

Phase 1, Engineering Validation is the first paid engagement in the CR1 development program. The work is engineering-led: an independent audit of the existing CAD, BOM, PCB gerbers, schematics, and prototype, a focused engineering workstream on the multi-market compliance pathway and PCB certification readiness, a DFM, DFA, and DFX engineering assessment across the mechanical and electronic architecture, supplier engineering engagement with indicative pricing, and a Development Roadmap that consolidates the output into a costed phase-by-phase pathway to qualified mass production.

Duration: approximately 6 working weeks from confirmation.

Phase 1 consists of the following six deliverables.

01

Engineering Kickoff Workshop

A working technical session with the Shield Works R&D team, not an introductory call. We walk through the CR1 product architecture, the existing CAD, BOM, PCB gerbers, schematics, and prototype build experience, Vinesh's commercial goals and target market certification priorities, and agree the engineering priorities and workstreams before work begins.

02

Independent CAD, BOM, and PCB Engineering Audit

Written, annotated audit of the provided STEP files, 2D drawings, bill of material, PCB gerbers, schematics, and the working prototype. Focus is on the aluminium frame and panel construction, the fan mounting and harness, the PCB design, and the integration with the certified PSU module. A value-engineering pass is included given the existing prototype build economics. Output: annotated engineering commentary and a ranked list of recommended design revisions.

03

Compliance Pathway and PCB Certification Readiness Study

Dedicated engineering workstream on the central technical question. The CR1 is a mains-powered consumer electrical device targeting seven plug variant markets through the certified Mean Well PSU. The workstream maps the certification stack required for each target market (US FCC, EU CE LVD and EMC, UK UKCA, AU RCM, and the additional markets supported by PSU plug variants), reviews the PCB for EMC readiness against the relevant standards, identifies design changes required at PCB and unit level to support compliance, and recommends a sequencing strategy for which markets to certify first and which to stage. Output: documented compliance roadmap with identified design changes and indicative testing pathway, carried forward into the Development Roadmap.

04

Preliminary DFM, DFA, and DFX Engineering Assessment

Written assessment covering DFM and DFA across the mechanical and electronic architecture, including the aluminium extrusion frame strategy, sheet metal fabrication and powder coat finish, fan mounting and daisy-chain wiring, filter retention and sealing geometry, PCB and switch integration, PSU integration, packaging direction, and a structured risk register with mitigations. Preliminary at this stage against analysis and supplier data; full DFM execution, drawing release, and supplier qualification testing sit in Phase 2.

05

Supplier Engineering Shortlist and Indicative Quotation

Qualified supplier shortlist drawn from the Shield Works supply chain and wider network, with first-round engineering engagement to confirm capability and capacity across aluminium extrusion, sheet metal fabrication and powder coat finishing, PCB assembly, and final unit assembly. Indicative unit pricing at multiple volume tiers (500 unit pilot, 5,000 unit run, and a larger volume tier), benchmarked against the shortlisted suppliers. Accuracy is subject to the defined level of readiness for manufacture; final unit costs are locked against specific supplier quotes as the Phase 2 development phases progress.

06

Development Roadmap (Full RTMP)

The 25 to 35 page consolidating document that carries the Phase 1 engineering output forward into Phase 2 and through to qualified mass production manufacture. This is the full Route to Market Plan for the CR1.

The Development Roadmap will include:

Phase timelines and phase management costs across the full development program.
Shield Works resource allocations and core deliverables across sampling, development, design optimisation (full DFM, DFA, DFX), prototyping, certification testing, pilot run manufacture, mass production, and scaled production.
Consolidated written output of the Phase 1 engineering work, including the CAD, BOM, and PCB audit findings, the compliance pathway workstream output, and the DFX assessment.
Component-level bill of materials with material specifications and qualified supplier direction.
Mechanical engineering and DFM plan covering frame, panels, fan integration, filter retention, and assembly sequence.
Electronic engineering plan covering PCB rework direction, harness, and PSU integration.
Certification pathway with indicative lab fees by market and a sequencing strategy for first-market certification.
Prototyping and iteration plan with validation gates.
Tooling strategy and indicative tooling investment direction.
Pilot run manufacture plan tied to the 500 unit crowdfunding production target.
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 CR1 development program. Phase 2 and subsequent development, certification, tooling, and production work is scoped and costed within the Development Roadmap for Vinesh's approval before any execution begins.

Phase 1 Fee — Engineering Validation

USD 5,000

Payable in full on project confirmation

04 — Exclusions

What Sits Outside Phase 1

The Phase 1 fee covers all six deliverables in Section 3, including engineering work, the CAD, BOM, and PCB audit, the compliance pathway workstream, DFX assessment, supplier engagement, indicative quotation, and the Development Roadmap. The following are excluded and would be scoped and costed within the Development Roadmap itself or addressed through specialist external partners coordinated by Shield Works.

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Full DFM execution, engineering drawing release, and supplier qualification testing.

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PCB rework and engineering execution beyond the audit and compliance readiness assessment.

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Industrial design refinement or any 3D CAD development work beyond the audit.

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Prototyping, sampling, and physical testing.

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Certification testing lab fees. Phase 1 maps the certification pathway and identifies the required testing; the lab fees themselves are paid by Flow Engineering directly to the testing labs identified and coordinated by Shield Works.

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Performance testing fees (CADR per GB/T 18801-2022 and acoustic noise per GB/T 4214.1-2017). Routed through accredited onshore testing labs and paid directly by Flow Engineering.

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Tooling, where applicable.

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Shipping costs for physical samples or prototypes between China and Hong Kong.

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Patent or utility model filing fees (guidance is included; filing costs are separate).

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Production unit costs.

Note on the post-Phase 1 model

once a supplier set is confirmed and production begins, C2W and Shield Works operate as Flow Engineering's manufacturing partner. Vinesh receives a single unit cost per CR1 unit 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 specifically designed to establish those unit costs with confidence before any production commitment is made.

05 — Payment Terms

Phase 1 Payment

Stage	Fee	Payment Trigger
Phase 1, Engineering Validation	USD 5,000	Payable in full on project confirmation

06 — Safeguards & Clarifications

How We Keep Phase 1 Honest

Scope changes

If requirements change materially during Phase 1 (for example, a change in the number of target certification markets included in the readiness study, or the addition of regulatory testing requirements), we will adjust cost and timeline accordingly and agree any changes before proceeding.

Quotation accuracy

The Indicative Quotation delivered as part of Phase 1 is subject to the level of readiness for manufacture. Final pricing is locked against specific supplier quotes inside the Phase 1 output and progressively refined through Phase 2 development.

Certification testing

Phase 1 maps the certification pathway, identifies required design changes, and recommends accredited labs for the testing program. The testing itself, the lab fees, and the certification timeline sit in Phase 2 and are quoted by the lab directly to Flow Engineering.

CAD, BOM, and PCB audit

Our review of the provided STEP files, BOM, PCB gerbers, and schematics will be independent and written. Where the design is sound, we will confirm it. Where revisions are required, we will recommend specific changes and explain the reasoning. The objective is to give Vinesh a defensible technical position from which to make the best commercial decision.

Intellectual property

Flow Engineering retains all intellectual property in the CR1 product, including design, BOM, and any derivative work produced under our engagement. Shield Works operates within an IP-secure, ISO-certified facility. An NNN agreement covering all third-party suppliers engaged on the project will be put in place before any external engagement begins.

Timelines

The 6 working week Phase 1 estimate assumes reasonable availability for the Engineering Kickoff Workshop and follow-up technical discussions during the engagement, and timely sharing of the CAD, BOM, PCB gerbers, schematics, and prototype with the Shield Works R&D team.

07 — Why C2W and Shield Works

Why C2W and Shield Works

Full-time dedicated project manager in our China HQ coordinating all suppliers, engineering resources, and the Flow Engineering team, with full visibility on who is making what and where.

In-house R&D, mechanical engineering, DFM and DFX, quality control, and audit resources, led by a mechanical engineer CEO (27 years of manufacturing experience) and a Head of R&D with over 12 years of China-based product engineering experience.

Over 20 years of proven track record delivering complex multi-component consumer products from China, with direct experience across aluminium extrusion, sheet metal fabrication, powder coat finishing, PCB assembly, and consumer electronics integration.

IP-secure, ISO-certified manufacturing facility (Shield Works, Zhuhai) available for sub-assembly integration, quality control, packaging, and warehousing.

Established supply chain across the CR1 component set, with Vinesh dealing with a single commercial counterparty for the all-in supply.

Transparent factory selection and direct supplier relationships. No hidden middlemen, no opaque quotes, no surprises on quality.

End-to-end capability from concept through to qualified mass production, with packaging and 3PL services available through the same group of companies.

Zhuhai facility easily reachable from Hong Kong via the bridge for direct factory visits during the program.

08 — Next Steps

From Confirmation to Phase 1 Delivery

01

Vinesh shares the CR1 CAD (STEP), 2D drawings, BOM, PCB gerbers, and schematics with the Shield Works R&D team.

02

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

03

C2W issues invoice for USD 5,000.

04

On receipt of payment, we schedule the Engineering Kickoff Workshop with the Shield Works R&D team.

05

Phase 1 output, including the Development Roadmap, delivered within approximately 6 working weeks of the Engineering Kickoff Workshop, including the full development program roadmap with costs and timelines for Vinesh's approval.

This proposal is non-binding at this stage and is intended to give Vinesh clarity on cost, structure, and what Phase 1 will actually produce. If you are happy with the direction, we can move to project confirmation at your convenience and proceed from there.

Best regards,

Mark Jacobs

CEO, C2W Group / Shield Works

9 June 2026