San Jose, CA
1. MOS Plastics (KS Group Division)
Address: 2308 Zanker Rd, San Jose, CA 95131
Phone: (408) 944-9407
Website: https://www.ksplastic.com
Founded: 1974
Employees: 50-99
Facility: 55,000 sq ft
Services:
Custom injection molding, insert molding, two-shot molding, overmolding, contract manufacturing, medical device assembly, ultrasonic welding, pad printing, cleanroom molding (Class 7 and 8)
Industries Served:
Medical devices, diagnostics, pharmaceuticals, life sciences, electronics, high-tech
Certifications: ISO 13485, FDA Registered
Highlight:
MOS Plastics is a Silicon Valley institution with over 50 years of medical device manufacturing expertise. Their 55,000 sq ft San Jose facility features Class 7 cleanrooms and 35 injection molding machines, making them a preferred contract manufacturer for medical device and diagnostic companies requiring precision components and regulatory compliance.
2. Knightsbridge Plastics Inc. (Viant Medical)
Located in Fremont, serving San Jose metro area
Address: 3075 Osgood Ct, Fremont, CA 94539
Phone: (510) 440-8444
Website: https://viantmedical.com (acquired by Viant Medical in November 2024)
Founded: 1982
Employees: 20-50
Facility: 20,000 sq ft
Services:
Precision plastic injection molding, in-house tooling and design, mold making, tight tolerance molding, quality assurance
Industries Served:
Medical devices, electronics, consumer products, automotive
Certifications: ISO 9001
Highlight:
Knightsbridge Plastics specialized in small to medium size tight tolerance parts from their 20,000 sq ft Fremont facility. In November 2024, the company was acquired by Viant Medical, expanding Viant’s medical device manufacturing footprint in the San Francisco Bay Area.
3. Plastikon Industries, Inc.
Located in Hayward, serving San Jose metro area
Address: 687 Sandoval Way, Hayward, CA 94544
Phone: (888) 538-9374
Website: https://www.plastikon.com
Employees: 199 at this location
Services:
Plastic injection molding, blow/fill/seal (BFS) aseptic filling, prototyping and product development, injection mold design and tooling, plastic thermoforming, cleanroom manufacturing, part decoration and assembly, warehouse logistics
Industries Served:
Healthcare, pharmaceuticals, medical devices
Certifications: ISO 9001, ISO 14001, ISO 13485, IATF 16949, MBE Certified
Highlight:
Plastikon Industries operates as a global leader in plastic injection molding with 12 worldwide facilities and over 1,300 team members. Their Hayward headquarters serves as a hub for healthcare and pharmaceutical manufacturing, leveraging Toyota-trained lean manufacturing principles and specialized blow/fill/seal capabilities for sterile packaging applications.
Columbus, OH
1. CORE Molding Technologies, Inc.
Address: 800 Manor Park Dr, Columbus, OH 43228
Phone: (614) 870-5000
Website: https://coremt.com
Founded: 1988
Employees: 1,001-5,000
Facility: 1.5 million sq ft (across multiple locations)
Services:
Compression molding (SMC), direct long-fiber thermoplastics (DLFT), resin transfer molding (RTM), structural foam injection molding, sheet molding compound manufacturing, spray-up, hand lay-up, custom material formulations, composite mold construction
Industries Served:
Heavy-duty trucks, powersports, building products, utilities, construction and agriculture equipment, industrial products
Certifications: ISO 9001, ISO 14001
Highlight:
CORE Molding Technologies is a publicly traded company (NYSE American: CMT) and leading engineered materials specialist focusing on large-format structural components. Their Columbus headquarters produces hoods and body panels for major truck manufacturers including Kenworth, Volvo, and PACCAR, with operations spanning 7 facilities across North America.
2. Precision Polymers, Inc.
Located in Reynoldsburg, serving Columbus metro area
Address: 6919 Americana Parkway, Reynoldsburg, OH 43068
Phone: (614) 322-9951
Website: https://precisionpolymers.com
Founded: 1999
Employees: 8-20
Facility: 25,000+ sq ft
Services:
Custom injection molding, precision tight tolerance molding, color matching, assembly services, tool and mold building, automation, tool maintenance, quality assurance
Industries Served:
Automotive, small appliances, electrical, industrial, utilities
Certifications: ISO 9001:2015
Highlight:
Precision Polymers has built a strong reputation serving automotive OEMs including Honda, Toyota, Ford, and Cadillac. Their 25,000+ sq ft Reynoldsburg facility features all-electric Milacron injection molding presses up to 275 tons, focusing on tight tolerance molding and meticulous color matching for engineering-grade resins.
3. Marne Plastics, LLC
Located in Grove City, serving Columbus metro area
Address: 3655 Brookham Dr., Suite F, Grove City, OH 43123
Phone: (614) 507-6537
Website: https://marneplastics.com
Email: info@marneplastics.com
Employees: 11-39
Facility: 58,000 sq ft
Services:
Custom injection molding, rapid prototyping, tool build management, part quality confirmation, secondary operations (assembly, embellishment, vibration welding, hotplate welding), inventory management
Industries Served:
Automotive, consumer goods, packaging
Certifications: ISO 9001:2015
Highlight:
Marne Plastics operates from a climate-controlled 58,000 sq ft facility with 15-18 injection molding machines ranging from 100 to 550 tons. The company has earned recognition from NIFCO for exceptional quality, responsiveness, and 100% on-time delivery, specializing in materials including ABS, PP, TPO/TPE, and PA6/PA66 with glass or talc.
Charlotte, NC
1. Delta Mold, Inc.
Address: 9415 Stockport Place, Charlotte, NC 28273
Phone: (704) 588-6600
Website: https://deltamold.com
Email: info@deltamold.com
Founded: 1978
Employees: 80-125
Facility: 70,000 sq ft (two plants)
Services:
Plastic injection mold design and manufacturing, compression mold building, stack molds, RIM tools, mold repair, injection molding prototyping, feasibility studies, 3D modeling, sampling
Industries Served:
Consumer products, automotive, industrial, medical, packaging, appliances, agriculture, lawn and garden, outdoor recreation, transportation
Certifications: ISO 9001:2015
Highlight:
Delta Mold is the largest product tool shop in the Southeast, manufacturing over 17,500 unique molds since 1978. The family-owned company operates two ISO-certified facilities totaling 70,000 sq ft with 24/7 production capability, building injection molds from 50 to 6,600 tons including boat hull-sized tooling.
2. Double O Plastics, Inc.
Located in Concord, serving Charlotte metro area
Address: 981 Biscayne Dr, Concord, NC 28027
Phone: (704) 788-8517
Website: https://www.doubleoplastics.net
Founded: 1990
Employees: 39
Services:
Custom injection molding, short run production, high volume production, material selection consulting, mold production and maintenance, on-site assembly, inventory management, safety stock programs, secondary operations, custom packaging and labeling
Industries Served:
General manufacturing, consumer products, industrial
Highlight:
Double O Plastics has served the plastic industry since 1990 and was featured in Plastics News and The Charlotte Observer. With 13 dedicated machines up to 730 tons, they specialize in both short lead time production runs and high volume capacity, offering comprehensive inventory management and safety stock programs to keep customer operations running efficiently.
3. Bull Engineered Products
Address: 12001 Steele Creek Road, Charlotte, NC 28273
Phone: (866) 752-2855
Website: https://bullep.com
Founded: 2001
Facility: 65,000+ sq ft
Services:
Injection molding, rotational molding, part development, rapid prototyping, mold making, mold repair, turnkey process management, program management, ultrasonic welding, corona treatment, gluing, pad printing, secondary assembly, warehousing, drop shipping, vendor managed inventory, KanBan management
Industries Served:
Consumer products, industrial, automotive, agricultural equipment
Certifications: ISO 9001:2015
Highlight:
Bull Engineered Products combines 450+ years of collective plastic and mold making experience with 50+ years of product development expertise. Their 65,000+ sq ft facility at the intersection of I-77, I-85, and I-485 provides strategic access to the Southeastern United States, offering both injection and rotational molding with in-house mold fabrication capabilities.
Notes
Research across these three metro areas reveals distinct regional specializations. San Jose companies focus heavily on medical devices and high-tech applications, leveraging Silicon Valley’s innovation ecosystem and cleanroom capabilities. Columbus manufacturers emphasize automotive supply chain integration, with companies like CORE Molding serving major truck OEMs and Precision Polymers supplying parts to Honda and Toyota. Charlotte’s injection molding sector serves a broader industrial base, with Delta Mold positioning itself as the Southeast’s largest tool shop and Bull Engineered Products offering combined injection and rotational molding under one roof.
Several companies in the San Jose metro area (Fremont, Hayward) operate within the broader Bay Area manufacturing corridor, where proximity to medical device startups and tech companies drives demand for precision cleanroom molding. The Columbus region benefits from Ohio’s strong manufacturing heritage, with companies maintaining ISO certifications and lean manufacturing practices developed through automotive industry relationships.
Research conducted January 2026. Verify all information directly with companies before business engagement.