H&L Manufacturing | Wire Harness & Contract Manufacturing
Custom wire harness assembly, overmolding, control panels, and general assembly. Family-owned since 1967 in Middleville, Michigan. ISO 9001:2015 certified, UL Approved, IPC/WHMA-A-620 compliant.
Our Services
- Wire Harness Manufacturing — Custom wire harnesses from prototype to high-volume production
- Overmolding — Sealed, ruggedized overmolded connectors for harsh environments
- Control Panel Assembly — Complete panel builds with UL 508A compliance
- General Assembly — Box builds, sub-assemblies, kitting, and fulfillment
- Prototyping & 3D Printing — Rapid prototypes with engineering feedback
Why H&L
- Vertically Integrated: Wire harness, overmolding, panel assembly, and 3D printing under one roof
- American Made: Manufactured in Middleville, Michigan
- Prototype to Production: Scale without switching vendors
- Quality Obsessed: Every harness tested, every assembly inspected. IPC/WHMA-A-620 standards
By the Numbers
- 59+ Years in Business
- 54,000+ Sq Ft Facility
- 100% Electrically Tested
- ISO 9001:2015 Certified
Industries We Serve
- Automotive
- Consumer & Commercial Products
- RV & Recreational
- Utility Trailers & Vehicles
- Industrial Controls & Automation
- Agriculture & Heavy Equipment
Frequently Asked Questions
- What does H&L Manufacturing do?
- H&L Manufacturing is a full-service contract manufacturer specializing in wire harness assembly, overmolding, control panel builds, general assembly, and prototyping — all from our facility in Middleville, Michigan.
- Where is H&L located?
- We're located at 900 E Main St, Middleville, MI 49333. Our 54,000+ square foot facility houses all of our manufacturing capabilities under one roof.
- What quality standards does H&L follow?
- We follow IPC/WHMA-A-620 workmanship standards. Every wire harness is electrically tested and every assembly is inspected before it ships.
- How do I request a quote?
- Simply visit our Request a Quote page and upload your drawings, specs, or BOM. Our team will review your project and respond with a competitive quote.