Product Assembly Services from China

One-stop assembly from a trusted China manufacturer. We turn loose parts into finished, tested, packaged products — ready to sell. Get a factory-direct quote within 24 hours.

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The Problem We Solve

Tired of juggling multiple suppliers for one product?

You design a great product. Then the hard part starts — coordinating a dozen vendors, chasing parts, fixing bad fits, and dealing with delays.

What buyers struggle with

  • Parts from different factories do not fit together
  • Hidden assembly costs pop up after you order
  • No one takes responsibility when something goes wrong
  • Long lead times because parts ship between vendors
  • Quality issues found too late — after you receive the goods
  • Communication gaps with overseas suppliers

How YiguProto fixes it

  • One factory makes parts AND assembles them — accountability in one place
  • Clear, itemized pricing up front — no surprise charges
  • In-house QC at every step, not just at the end
  • Faster lead times because parts never leave our floor
  • 100% functional testing before shipment
  • English-speaking engineers who reply within hours
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China assembly service manufacturer factory
Full product assembly at YiguProto's China factory

What We Do

From loose parts to finished products, all under one roof

YiguProto is a China-based manufacturer and supplier that does more than make parts. Our assembly service takes plastic, metal, electronic and off-the-shelf components and builds them into complete products — tested, packaged and ready for your customer.

Whether you need a simple screw-together sub-assembly or a complex electro-mechanical finished product, our factory team handles every step. We work with startups, OEMs and product brands across North America, Europe and beyond.

No MOQ pressure. We build one-off prototypes, small bridge runs and full production volumes from the same team and floor.

  • Manufacture parts AND assemble them in-house
  • Source hardware, electronics and packaging for you
  • Test every unit before it ships
  • Quote within 24 hours — clear, itemized, factory-direct
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Our Capabilities

Complete assembly solutions for every product type

We combine hands-on mechanical assembly with a full set of plastic and metal joining methods. Here is exactly what our China factory can do for you.

Mechanical Assembly

Putting parts together the right way — with the right tools, the right torque, and the right checks.

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Full Product Assembly

We assemble every part — plastic housings, metal brackets, PCBs, cables, screws, labels and packaging — into a finished product that works out of the box.

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Sub-Assembly

Modular sub-assemblies built and tested separately, then delivered ready to drop into your larger build. Saves you time on your final assembly line.

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Hardware Insertion

Threaded inserts, standoffs, pins, clips, nuts, screws and springs — pressed, heat-set or ultrasonically installed to spec, every time.

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PCB & Electronics Integration

We wire, solder and connect circuit boards, switches, connectors, displays and battery packs. Every unit gets a power-on and functional test.

📦

Kitting & Packaging

Custom retail packaging, blister packs, instruction manuals, labels, barcodes and carton marking. Your products arrive shelf-ready.

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Incoming QC & Parts Sourcing

We inspect every component (yours or ours) before it hits the assembly line. Need help sourcing parts in China? We handle that too.

Joining Technologies

Strong, clean bonds for plastic and metal parts — no messy glue, no visible screws when you do not want them.

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Ultrasonic Welding

High-frequency vibration creates strong, clean, hermetic seals between thermoplastic parts. Perfect for fluid containers, consumer goods and clean-looking assemblies.

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Heat Staking

Permanently joins dissimilar materials — plastic to metal, plastic to PCB — by melting molded posts. No extra fasteners needed, very repeatable.

🌎

Hot Plate Welding

Thermal fusion for large or irregular plastic joints. Great for bigger parts, tanks and structural assemblies that need a strong, leak-proof bond.

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Spin / Rotational Welding

Friction welding for round and cylindrical plastic parts. Fast, consistent, leak-proof joints at production speed with little tooling cost.

🧰

Adhesive Bonding & Gluing

Industrial-grade adhesives for tricky material combinations. Metered mixing and jigged curing for consistent bond strength on every unit.

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Mechanical Fastening

Screws, snaps, clips, rivets and press fits. We use torque-controlled drivers and custom jigs to avoid damage and ensure every fastener is set correctly.

How We Work With You

Three flexible assembly options — pick what fits your project

Every buyer's situation is different. Some want us to do everything. Others want to supply their own parts. We adapt to your needs.

OPTION 1

Full Turnkey

We make the parts, source the hardware and electronics, assemble, test, package and ship. You just send us the design and approve samples. Easiest option — one contact, one invoice, zero hassle.

OPTION 2

Partial Turnkey

We make some parts in-house, and you supply others (for example, custom electronics or branded components). We receive your parts, inspect them, assemble everything, test and ship.

OPTION 3

Assembly Only

You send us all components, and we do the assembly, QC, testing, packaging and shipping. You control sourcing, we provide skilled labor, clean workflow and reliable output.

Tell Us What You Need

Capability Specs

Assembly capabilities at a glance

Real numbers so you can spec your project with confidence.

CategoryCapability
Service typesFull product assembly, sub-assembly, kitting, packaging
Materials handledPlastics (ABS, PC, PP, POM, PA, PMMA, PEEK), metals, electronics, rubber, silicone
Joining methodsUltrasonic welding, heat staking, hot plate welding, spin welding, gluing, screwing, snap-fit, press-fit
Electronics workPCB wiring, soldering, connector assembly, battery integration, functional testing
Part size rangeSmall precision parts up to 800 mm assemblies
Volume range1 unit (prototype) to 100,000+ units (production)
Lead time3–15 business days (depending on complexity and quantity)
TestingFunctional test, visual inspection, dimensional check, pressure/leak test (when needed)
Certifications supportedRoHS, CE, FCC, REACH — documentation and test support
ShippingWorldwide — express, air, sea; DDP or FOB your choice

Industries

Products we assemble every day

Our China assembly company has built finished products for buyers across many industries. Here are the sectors we know well.

Consumer Electronics
Home Appliances
Automotive Parts
Medical Devices
Industrial Equipment
Smart Home Products
Toys & Hobby
Sports & Outdoors
Lighting Products
Pet Products
Beauty & Personal Care
New Energy

Why YiguProto

Why global buyers choose our China factory

There are plenty of assembly suppliers in China. Here is what makes working with YiguProto different.

✉

Real factory, not a trading company

We own and run our own assembly floor in Dongguan, China. You deal directly with the people making your product. No middleman markup, no broken telephone.

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15+ years of manufacturing experience

Our engineers and assembly technicians have built products for hundreds of international clients. We have seen (and solved) most problems before they become your problem.

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One-stop shop from design to delivery

DFM review, prototyping, tooling, molding, machining, assembly, testing, packaging, shipping. One company handles the whole project. Less risk, faster turnaround.

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NDA protection & IP security

We sign NDAs before sharing any project details. Your files, designs and product ideas stay with us — no outsourcing without your written approval.

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Strict quality control

Every assembly has written work instructions (SOPs), in-process checks, and a final inspection before shipping. Inspection reports and test data are available on request.

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English-speaking engineers

No lost-in-translation issues. Your project is managed by an engineer who speaks your language, replies within hours, and sends photo and video updates during production.

15+
Years in manufacturing
24h
Quote response time
30+
Countries served
ISO 9001
Quality standard

How It Works

From your files to finished products in 5 simple steps

A clear, predictable process so you always know where your project stands.

1

Send Us Your Project

Share your BOM, drawings, STEP files, samples or even a sketch. Tell us quantities and target timing.

2

Free DFM Review & Quote

Our engineers check your design for assembly issues. You get a clear, itemized quote within 24 hours.

3

Sample Build & Approval

We make first articles or a pilot run, send photos/videos, and ship samples for your approval before mass production.

4

Production & Assembly

Parts are made or received, inspected, assembled per SOPs, and tested at our China factory.

5

Final QC & Ship

100% final inspection, custom packaging, and direct shipping to your door with tracking and inspection reports.

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Quality Assurance

We do not ship until it works

Quality problems from overseas suppliers cost you time, money and customer trust. That is why quality is built into every step of our assembly process — not checked once at the end.

  • Incoming inspection: Every part (made in-house or supplied) is checked before assembly
  • In-process checks: Operators verify fit, torque and function at each station
  • Functional testing: Power-on, motion, pressure, leak or load testing as your product needs
  • Final inspection: 100% visual and dimensional check before packing
  • Traceability: Batch records and inspection reports kept on file for every order
  • Warranty support: If a defect slips through, we make it right — fast
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Check 1Incoming parts
Check 2Assembly fit
Check 3Functional test
Check 4Cosmetic review
Check 5Packaging check
Check 6Shipment audit
Six inspection gates on every product

FAQ

Assembly — Frequently Asked Questions

Straight answers to the questions buyers ask us most often.

We offer full product assembly, sub-assembly, mechanical fastening, ultrasonic welding, heat staking, hardware insertion, PCB integration, functional testing, packaging and worldwide shipping. We assemble plastic, metal and electronic parts into finished, ready-to-sell products.
Send us your BOM, drawings, 3D files (STEP/STP/IGES) or samples. Most quotes come back within 24 hours on business days. Complex projects may take a little longer, but we always confirm receipt fast and tell you when to expect pricing.
Absolutely. You can free-issue some or all components, and we handle inspection, assembly, QC, testing and packaging. Many customers send us their branded electronics or custom parts. We can also source standard and custom parts for you through our trusted supplier network in China.
Yes. All customer files and project details are treated as confidential from day one. We sign NDAs upon request before any engineering discussion begins. Your designs stay with us and are never shared.
There is no strict MOQ. We support prototype builds (1–10 units), small bridge runs (50–500 units), and full high-volume production (10,000+ units). Tell us your project, and we will recommend the right approach.
Typical lead time is 5–15 business days depending on complexity, quantity and part readiness. Prototype or small-batch assembly can often ship in 3–5 days. We always confirm exact timing in your quote and update you if anything changes.
Yes. Every assembled unit goes through incoming parts checks, in-process verification, functional testing (power-on, motion, leak, load, etc. as needed), and a final visual and dimensional inspection before it leaves our factory. Inspection reports are available on request.
Yes. We offer custom retail packaging, blister packs, instruction inserts, labels, barcodes, UPC stickers, inner cartons and master cartons. We ship worldwide via express (DHL/FedEx/UPS), air freight or sea freight — DDP or FOB, your choice.
Yes. We can provide material declarations, RoHS/REACH compliance documentation, and support CE, FCC and other testing through our partner labs. Tell us what certifications your market requires, and we will build compliance into the process.
Yes. Our engineers review every design for assembly and manufacturing issues before we quote. We point out potential fit problems, tolerance stack-ups, cost-saving opportunities and design improvements — free of charge.

Ready to get your product assembled the right way?

Send us your files, BOM or product idea. Get a free DFM review and a factory-direct quote within 24 hours from a trusted China assembly manufacturer.

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