Need a specific city or state? Want to email them directly?
Search, get contacts, and send outreach — all in one place.
Last updated: January 2026
This directory lists 45 lsr molding companies across the United States, from specialized prototyping shops adept at rapid iterations to large-scale contract manufacturers focused on high-volume production of intricate components.
Buyers frequently turn to LSR molders to solve challenges around sealing, cushioning, insulation, and biocompatibility, often for applications demanding extreme temperature resistance or chemical inertness. The inherent elastomeric properties of LSR, combined with precision two-shot molding or overmolding capabilities, allow for integrated solutions that reduce assembly costs and improve product performance in areas where traditional thermoplastics or thermosets fall short.
The spectrum of LSR suppliers varies considerably, encompassing those specializing solely in medical-grade components within ISO Class 7 or 8 cleanrooms, to general industrial molders, and even vertically integrated companies that perform in-house tooling development and assembly. Distinguishing factors often include their core competence in specific material durometer ranges, their preferred tooling approach (e.g., cold runner systems), and their capacity for secondary operations like automated deflashing or pad printing.
To effectively engage with these suppliers, buyers should arrive prepared with detailed CAD models, clear material specifications (including specific LSR grades and Shore A hardness), anticipated annual volumes, and defined critical-to-quality (CTQ) features. Reputable molders expect thorough Design for Manufacturability (DFM) reviews and transparency regarding end-use application environments to optimize tooling and process parameters from the outset.
45 companies nationwide
Based in Leominster, MA, Beacon MedTech Solutions specializes in liquid silicone rubber (LSR) injection molding. The company provides comprehensive expertise in part design and precision molding, primarily serving the medical device industry with high-quality components and solutions.
Casco Bay Molding is an ISO 13485:2016 Certified product development and injection molding facility in Sanford, ME. They offer in-house tooling and specialize in high-volume silicone and thermoplastic production, including LSR parts. Their expertise focuses on Class I and II medical device components.
Clark Rubber & Plastic Co., based in Mentor, OH, provides custom rubber and plastic solutions. The company specializes in various molding processes, including liquid silicone rubber (LSR) injection molding, alongside thermoplastic, compression, and transfer molding, supported by additional fabrication and assembly services.
Based in Dayton, OH, C & M Rubber Co. specializes in custom rubber fabrication, compounding, and molding of silicone and other thermosetting elastomers. They provide liquid injection molding, prototyping, and silicone to metal bonding services for military, medical, food service, aerospace, and high-tech industries. The company is ISO 9001:2015 Certified.
Based in Cleveland, OH, Custom Rubber Corporation manufactures custom molded rubber components for various industries. The company emphasizes quality, on-time delivery, and customer experience throughout the design-to-delivery process. All products are proudly made in the USA.
Dymotek specializes in liquid silicone molding, efficiently producing ultra-precision liquid silicone rubber parts in various configurations. They also provide advanced injection molding processes, including 2-Shot molding, multi-material engineering solutions combining plastic and silicone rubber, assembly, and fulfillment services.
Elastostar Rubber Corporation, based in Plain City, OH, manufactures custom extruded and precision-molded silicone components. The company is ISO 9001:2015, AS9100D, and IATF 16949 certified. They provide high-quality rubber products for aerospace, medical equipment, automotive, and food industries, offering platinum cured, food, and medical grade materials.
Based in Corona, CA, Elastomer Technologies, Inc. provides customer-tailored molding and die-cutting solutions. They specialize in various elastomer manufacturing capabilities, including compression, transfer, prototype, and liquid injection molding. With extensive experience, they produce complex engineered parts for diverse industries, notably the medical sector.
G&F Precision Molding, Inc., based in Fiskdale, MA, specializes in custom silicone molding solutions. Serving the life science, medical device, and pharmaceutical industries, the company offers comprehensive capabilities from concept to execution for challenging projects.
Based in San Clemente, CA, IRP Medical specializes in LSR and LIM molding, providing critical-to-function elastomeric solutions for medical devices. The company offers scalable manufacturing from prototype to high-volume production, holding ISO 13485 certification and FDA registration for precision components.
Based in Lancaster, NY, Moldtech is a manufacturer of custom rubber molded products. The company specializes in rubber injection molding, overmolding, and LSR and HCR silicone molding. They produce components like boots, bellows, seals, gaskets, and wheels for various industrial applications.
Based in East Troy, WI, Moxness is a technology-driven custom manufacturer specializing in Liquid Silicone Rubber (LSR) and LSR Overmold parts and components. They serve diverse industrial, commercial, and consumer applications. Moxness provides precision silicone rubber products with extensive engineering experience and a state-of-the-art facility.
Based in Burleson, TX, Newnak's Plastics LLC is a family-owned US manufacturer providing custom plastic molding solutions. They specialize in molding silicone, polyester, urethane, ABS, and styrene. Services include silicone mold making, resin casting, thermal vacuum forming, centrifugal casting, and 3D printing.
Based in Canal Winchester, OH, Olan Plastics Inc. provides injection and insert molding services for various industries. The company molds a wide variety of resins and rubber, leveraging over 40 years of industry experience. They also offer subassembly, consulting, warehousing, and shipping solutions.
Based in El Paso, TX, Plastic Molding Technology specializes in custom plastic injection molding, with dedicated in-house Liquid Silicone Rubber (LSR) manufacturing capabilities. The company provides complex, high-precision components, processing a wide range of thermoplastic and thermoset materials for diverse industrial and commercial applications.
Based in Plymouth, MN, Promed Molding is a contract manufacturer specializing in complex molded silicone and plastic components and assemblies. They serve highly regulated industries such as medical devices, pharmaceuticals, and security. Services range from prototype through production, including design, material selection, tooling, and process development for critical parts.
Based in Santa Fe Springs, CA, RD Rubber Technology specializes in precision custom rubber molding and manufacturing. They offer Liquid Injection Molding (LIM/LSR), compression, and injection molding, alongside cleanroom services. The company provides engineering, product development, and prototyping for aerospace, defense, and medical device industries.
Based in Minneapolis, MN, Robinson Rubber Products is an ISO 9001:2015 certified custom molding manufacturer of elastomeric and thermoplastic components. They specialize in liquid silicone rubber (LSR) molding, insert/over molding, and offer design assistance with value-add services like assembly and packaging.
L.W. Reinhold Plastics, based in South Gate, CA, specializes in custom injection, compression, and transfer molding of thermosets and thermoplastics. They offer up to 300 tons of press capacity. The company provides product development, engineering, and prototyping services, holding ISO 9001:2015 and ITAR certifications.
Seaway Plastics Engineering offers direct liquid silicone rubber (LSR) and thermoplastic injection molding services for high-quality custom components. They provide in-house mold design, tooling, and ISO Class 7 & 8 cleanroom molding and assembly. Seaway Plastics primarily serves the medical and other regulated industries from Port Richey, FL.
Based in Miramar, FL, Simtec Silicone Parts specializes in high-quality liquid silicone rubber (LSR) and multi-shot molded components. They provide turnkey custom solutions with fully-automated LSR injection molding technologies and an ISO-certified class 8 clean room. The company serves medical, healthcare, mobility, industrial, and consumer markets for high-volume production.
Based in Newport News, VA, SiTech (Silicone Technology Corp.) specializes exclusively in Liquid Silicone Rubber (LSR) injection molding. They produce custom silicone keypads and components for aerospace, industrial, marine, and medical industries. SiTech offers rapid prototyping and application engineering from its US facility.
Based in Philadelphia, PA, Stockwell Elastomerics specializes in custom silicone gasket solutions and provides high-performance materials for the technology equipment sector. They offer problem-solving engineering support, including material selection and manufacturing process guidance. The company's operations include injection molding of liquid silicone rubber (LSR) as a growing segment.
Based in Skaneateles, NY, Tessy Plastics Solutions is a custom contract manufacturer specializing in plastics processing. They offer comprehensive end-to-end capabilities, including injection mold design, micro molding, over molding, and LSR molding. The company serves medical, pharmaceutical, and consumer industries, also providing precision tooling and automation design.
Based in Trenton, TX, Trenton Plastics specializes in plastic and rubber molding, including injection, transfer, and compression processes. They offer customized solutions for various engineered resins, serving industrial clients in aerospace, medical, oil & gas, and electronics with custom parts.
Utah Medical Products specializes in silicone and thermoplastic molding for complex medical and non-medical applications. They manufacture a range of proprietary medical devices, including catheters for cervical ripening, suprapubic catheterization, enteral feeding, and uterine balloon tamponade.
WHK BioSystems, LLC is a global manufacturer specializing in high-quality injection molded and overmolded components for the biopharmaceutical and life science industries. They produce single-use process components, custom tube kits, and bottle assemblies for critical fluid management. Capabilities include molding platinum-cured silicone and TPE sanitary connections for various applications.
Nissha Medical Technologies offers end-to-end design, development, and manufacturing for single-use medical technologies. Based in Buffalo, NY, they specialize in advanced capabilities like isometric micro molding solutions, often utilizing medical grade silicone. Their expertise supports customers in bringing innovative medical devices to market efficiently.
Based in Worcester, MA, Jefferson Rubber Works, Inc. provides custom rubber molding services, including liquid silicone injection molding (LSR). Since 1975, they have offered high-volume, precision manufacturing with advanced mold-making techniques. The company delivers tailored solutions for diverse industrial and OEM client needs.
Prudent American Technologies manufactures custom silicone products, from small to medium sizes, in various shapes. Operating in a special clean room environment, they ensure contaminant-free silicone parts of varied design, specializing in high-quality silicone molding for diverse applications.
Based in Ankeny, IA, Accumold provides high-volume precision micro molding and tooling. With 40 years experience, they produce extremely small, high-precision parts, including LSR molding for optical micro components. Accumold serves medical, micro electronics, and polymer optics markets.
Based in Grand Prairie, TX, Advanced Rubber Molding specializes in manufacturing custom rubber and silicone molded products. They offer various processes, including Liquid Silicone Rubber (LSR) molding, compression, and transfer molding. The company provides precision components for diverse industrial and commercial applications.
EVCO Plastics is a global contract manufacturer specializing in plastic injection molding. With several manufacturing facilities across the United States, including locations in Wisconsin and Georgia, they offer comprehensive services from initial design collaboration to the production of fully formed plastic components. The company provides custom manufacturing opportunities for complex part geometries.
Extreme Molding & Assembly, located in Menands, NY, provides expert silicone injection molding services. Specializing in Liquid Silicone Rubber (LSR) molding, the company serves the medical, infant, and consumer product markets. They offer full-service production, including assembly, packaging, and fulfillment for complex silicone components.
Based in Costa Mesa, CA, JG Plastics Group LLC offers comprehensive thermoset and thermoplastic molding services. Leveraging decades of mold making and injection molding expertise, they utilize scientific molding principles to produce demanding, close tolerance parts. Their capabilities include constructing precision tooling.
McElroy Plastics, Inc., based in Troup, TX, specializes in custom injection molding, offering both thermoplastic and liquid silicone rubber (LSR) services. They provide comprehensive molding capabilities including overmolding, insert molding, prototyping, and tooling, serving diverse industrial clients with precision parts.
Minnesota Rubber & Plastics provides custom LSR design, prototyping, and manufacturing for complex components. Specializing in advanced materials science and global manufacturing, they solve challenging sealing and component needs for medical devices, water food & beverage, and other demanding industries. They also offer fully functional product prototyping.
Based in Shakopee, MN, Rubber Industries, Inc. specializes in custom molded rubber, silicone, and Liquid Silicone Rubber (LSR) parts. With over 55 years of experience, they provide rapid prototyping, precision molding, and custom tooling for both prototype and production. The company is ISO 9001:2015 certified.
Based in Latrobe, PA, Technimark is a global manufacturing partner specializing in precision injection molding, including liquid silicone rubber (LSR) molding. They offer complex assembly and contract manufacturing for Healthcare, Consumer Health, Consumer Packaging, and Specialty Industrial sectors, delivering high-precision parts.
Based in Houston, TX, Thermo-Mold Inc. specializes in custom plastic injection molding, now also offering Liquid Silicone Rubber (LSR) molding services. They provide comprehensive capabilities including product design, engineering, tooling design, fabrication, and assembly to meet diverse manufacturing needs for various industries.
Freudenberg Medical is a contract design and manufacturing organization (CDMO) specializing in medical and pharmaceutical innovation. They provide vertically integrated capabilities, including precision molding utilizing liquid silicone rubber (LSR) and high-performance thermoplastics. The company offers end-to-end support from design to full-scale production.
Based in Anaheim, CA, Konark Silicones is a manufacturer specializing in LSR and silicone injection molding solutions. They provide comprehensive services from engineering silicone part design, CAD, and material selection to mold design, prototyping, and high-quality silicone parts production. They offer complete project management for industrial clients.
Based in Gardena, CA, Dr. Nionz, Inc. specializes in new product development and advanced manufacturing. They provide precision injection molding for both thermoplastic and silicone (LSR) materials. The company offers turnkey solutions, from concept to commercialization, for medical, dental, cosmetic, and industrial sectors.
Rosti specializes in high-precision plastic injection molding and contract manufacturing services, delivering top-quality LSR products. With over 75 years of experience, the company operates globally, including US facilities in North Carolina, Utah, and Wisconsin. They partner with customers through the entire production cycle.
Wise Plastics, based in Milwaukee, WI, specializes in custom plastic injection molding, offering medical-grade Liquid Silicone Rubber (LSR) capabilities. They provide manufacturing solutions for critical medical device components, leveraging expertise in biocompatible materials and a wide range of LSR applications.
Found what you're looking for? Unlock 30 emails and 37 phones.
LIM tooling typically requires more precise machining and highly polished surfaces to manage LSR's low viscosity and prevent flash. Cold runner systems are common to keep the silicone uncured until it enters the hot mold cavity, and often, a vacuum assist is used to eliminate air bubbles for critical parts.
LSR's inherent material shrinkage (often 2-4%) after curing, combined with its elastomeric properties, makes achieving very tight tolerances challenging. Success depends on meticulous tool design, precise temperature control, gate location optimization, and experienced process engineers who understand post-mold deformation.
Multi-shot LSR molding is ideal when you need to combine the soft, flexible properties of LSR with a rigid substrate (plastic or metal) in a single, integrated component. This process eliminates secondary assembly steps, improves seal integrity, and is common for applications like sealed enclosures, ergonomic grips, or medical wearables.
Beyond standard quality checks, LSR molding often involves advanced inspection for micro-flash, precise durometer testing, post-cure verification, and rigorous testing for cleanliness and biocompatibility (e.g., extractables and leachables). Cleanroom manufacturing (ISO Class 7/8) is often mandatory, with strict particulate control and visual inspection for defects.
LSR tooling costs can range significantly, from tens of thousands for simple, single-cavity tools to hundreds of thousands for complex, multi-cavity tools with automated cold runners. Key drivers include the number of cavities, part complexity, required surface finish, hot/cold runner system complexity, and the need for hardened tool steel or specialized inserts.
DFM for LSR focuses on optimizing part design to account for the unique properties of liquid silicone rubber and the LIM process. This includes considerations for uniform wall thickness, radii to prevent stress concentrations, proper draft angles for demolding, gate location to minimize flash, and venting strategies. It's critical because slight design flaws can lead to significant quality issues like voids, knit lines, or excessive flash that are expensive to fix downstream.