Stockwell Elastomerics

What Stockwell Elastomerics does

Stockwell Elastomerics is a Philadelphia-based custom manufacturer of silicone elastomer components, founded in 1919 as Stockwell Rubber Company and renamed in 2005 to reflect its current specialization. The company fabricates silicone gaskets, pads, EMI shielding materials, thermal interface materials, conductive elastomers, and molded parts using closed cell silicone sponge, silicone foam, solid sheets, fluorosilicone (FVMQ), platinum-cured HCR silicone, liquid silicone rubber (LSR), and space-grade silicone materials. Manufacturing capabilities include die cutting, waterjet cutting, laser cutting, flash cutting, compression molding, liquid silicone injection molding, and adhesive lamination, all performed at a single ITAR-registered Philadelphia facility (Cage Code 87585). The company maintains an inventory of 399 different solid silicones and 699 unique items to support custom fabricated-to-order production.

The company operates a direct B2B enterprise sales model with all pricing handled via quote-based requests and no public pricing disclosed. Revenue derives from custom gasket manufacturing to customer specifications, stocked off-the-shelf products (gasket tape, foam port plugs, connector gaskets), and material sales in sheet and roll form. Customer segments span electronics and electrical equipment (primary; analytical instrumentation, portable data devices, telecom, ruggedized equipment, LED lighting, renewable energy, EV charging stations), medical devices (USP Class VI), aerospace and defense (MIL-DTL specifications, ITAR, ASTM E595 low outgassing for space), food processing (FDA 21 CFR 177.2600), and industrial/energy applications (BESS, fuel cells, semiconductor, robotics). No end-customer logos are publicly disclosed.

The company is employee-owned under an ESOP structure, in its third generation of family ownership, with technical differentiation anchored by authorized converter partnerships with Saint-Gobain (NORSEAL), Rogers Corporation (BISCO silicone foams), and 3M, plus a strategic vendor relationship with Specialty Silicone Products for space-grade materials and a technology partnership with Lynxter. Recent capability additions include the Lynxter S300X silicone 3D printing platform, which reduces prototype validation timelines from weeks to days, and a website-based AI assistant for customer engagement. Stockwell holds an extensive regulatory certification portfolio across medical, food contact, defense, and space applications.

Name

Stockwell Elastomerics

Legal name

Stockwell Elastomerics

Website

https://stockwell.com

Company type

Private

Founded year

1919

Operating status

Operating

Headcount range

101–250 employees

Short description

Stockwell Elastomerics is a Philadelphia-based, employee-owned manufacturer of custom silicone gaskets, EMI shielding materials, thermal interface pads, and elastomeric components, serving electronics, medical, aerospace, defense, food processing, and industrial customers with a single-facility quote-based B2B model since 1919.

Ownership category

akta.pro rank

Product category

Silicone Elastomer Manufacturing

NAICS

Urethane and Other Foam Product (except Polystyrene) Manufacturing (326150), Synthetic Rubber Manufacturing (325212)

SIC

Gaskets, Packg & Sealg Devices & Rubber & Plastics Hose (3050), Fabricated Rubber Products, Nec (3060)

akta.pro primary industry

Seals, Gaskets & O-Rings (Industrial Elastomer) (IMANALAC)

akta.pro secondary industries

Aerospace Seals, Gaskets, O-Rings & Elastomeric Components (IMABANAF), Polymer Foams & Cellular Materials (PU Foams, EPS/XPS, Structural Foams) (IMAEANAL), Thermoformed Electronics & Appliance Components (IMANAHAG)

Keywords

• Silicone gasket manufacturing
• Custom elastomer fabrication
• EMI shielding gaskets
• Fluorosilicone components
• Silicone rubber materials

Headquarters

HQ city

Philadelphia

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Supply Chain, Operations, Technology or R&D, Marketing or Sales, Infrastructure

Revenue model

1. Custom Gasket Manufacturing: Custom fabrication of silicone gaskets, seals, and cushioning pads to customer specifications. Products are manufactured to order based on customer drawings and specifications, with no minimum order quantities for some items and standard sheets for prototyping.
2. Stocked/Off-the-Shelf Products: Standard stocked products including gasket tape, foam port plugs, and connector gaskets available for immediate delivery.
3. Material Sales: Sale of elastomer materials including silicone sponge, foam, solid sheets, and specialty compounds in sheet/roll form with various thicknesses and durometers.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels4 records

Core offering

Stockwell Elastomerics is a Philadelphia-based custom manufacturer of silicone elastomer components, including gaskets, EMI/RFI shielding gaskets, conductive elastomers, thermal interface pads, vibration dampening pads, and molded LSR parts. The company fabricates silicone sponge, foam, solid sheet, fluorosilicone, and space-grade silicone materials to customer specifications, serving technology-intensive industries with demanding sealing, cushioning, and protection requirements.

Product overview

Stockwell Elastomerics is a Philadelphia-based manufacturer with over 100 years of experience specializing in custom silicone elastomer products. The company's core portfolio centers on silicone-based materials including sponge, foam, solid sheet, liquid silicone rubber (LSR), fluorosilicone, platinum-cured HCR, and space-grade silicone. Their manufactured products include custom gaskets, EMI shielding gaskets, ESD protection products, thermal interface materials, and vibration dampening solutions. Manufacturing capabilities encompass die cutting, waterjet cutting, laser cutting, compression molding, liquid silicone injection molding, and adhesive lamination. The company serves technology-intensive industries including aerospace, defense, medical devices, electronics, telecommunications, and space applications.

Differentiator

Problem solved

Functional benefit

Products and services

• Silicone Sponge Closed cell silicone sponge materials offering robust sealing and cushioning for severe weather and demanding conditions, with operating temperatures from -100°F to 500°F. Used in enclosure gaskets, weather sealing, and industrial applications.
• Silicone Foam Flame retardant silicone foam elastomers from Rogers BISCO and Saint-Gobain NORSEAL product lines offering environmental protection, vibration dampening, and temperature range from -67°F to 392°F.
• Solid Silicone Sheet Non-cellular silicone rubber sheets available in thicknesses from .010" to .500" and 10 to 70 durometer Shore A, for industrial sealing applications.
• Fluorosilicone (FVMQ) Silicone with fluorine groups providing enhanced resistance to jet fuels, non-polar solvents, acids, and oils for demanding aerospace, automotive, and industrial applications.
• Platinum Cured Silicone / High Consistency Rubber (HCR) Ultra-pure platinum cured HCR silicone including SSP4749 Series for medical (USP Class VI) and food contact (FDA 21 CFR 177.2600) applications, and ESS4722 Series for industrial applications.
• Space Grade Silicone Specialized elastomers including SSP4716 (phenyl-based, flexible to -116°C) and SSP4734-XXLV (methyl-based, meeting ASTM E595 low outgassing standards) for spacecraft and space vehicle applications.
• Liquid Silicone Rubber (LSR) Moldable 2-part silicone elastomer with temperature range -58°F to 392°F and durometer range 10-80 Shore A, used for injection molding, sheet casting, and various industrial applications.
• Compression Molding Compounds Gum-based elastomers including silicone, fluorosilicone, and specialty electrically/thermally conductive compounds capable of meeting military and aerospace specifications.
• Custom Gaskets Custom fabricated gaskets including silicone gaskets, molded LSR parts, custom gasket strips, silicone pads, and silicone O-rings manufactured to customer specifications for technology equipment applications.
• EMI Gaskets Electrically conductive gaskets for electromagnetic interference (EMI/RFI) shielding, available in nickel-graphite, silver-plated aluminum, and Monel wire mesh formulations.
• Conductive Elastomers / Conductive Gasket Materials Electrically conductive materials engineered for EMI shielding and ESD protection, including nickel-graphite filled silicone, silver-plated aluminum filled silicone, and conductive foam products.
• Condux Plus Electrically Conductive Foam Low-density microcellular urethane foam with metalized coating for shielding, grounding and sealing applications, providing EMI attenuation (50dB between 300MHz and 10GHz) and dust sealing.
• ESD Protection Products Products including T62 conductive coated silicone sponge, SE65-CON conductive silicone, and Conpads for electrostatic discharge management and grounding in electronic enclosures.
• Thermal Gap Filler Pads Thermally conductive materials for thermal management applications, bridging air gaps between heat sources and heat sinks in electronic equipment.
• Vibration Dampening Pads Elastomeric pads for vibration isolation and shock absorption in electronic equipment and industrial applications.
• Adhesive Backed Gaskets Custom gaskets with pressure sensitive adhesive backings including acrylic, silicone, and combination adhesives for faster assembly during final installation.
• Gasket Tape Standard stocked gasket tape available for immediate delivery, used for sealing and weatherproofing applications.
• Gasket Assembly Services Gasket assembly techniques and services including corner bonding, dovetail joints, and custom assembly for enclosure gaskets and large parts.
• Material Testing Services Material testing capabilities including compression set testing, physical property testing, and specification compliance verification.
• Prototype Silicone Gaskets & Pads Rapid prototyping services including waterjet cut prototypes, cut-to-size parts, and quick-turn manufacturing for design validation.
• Fabric Reinforced Materials Reinforced silicone products with high tensile strength and dimensional stability, including silicone coated fabrics, EMI sheet, PTFE and fluorosilicone sheets, and thermally conductive sheets.

Segments5 records

Ideal customer profiles4 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature6 records

Partnerships

Five partnerships are on record, tiered core.

• Saint-GobaincoreTechnology or IntegrationAuthorized Saint-Gobain converter offering the full product line of NORSEAL (formerly COHRlastic) closed cell silicone sponge materials and silicone foam products. Products include flame rated materials, thermally conductive sponges, and fluorosilicone variants.
• Rogers CorporationcoreTechnology or IntegrationRogers Corporation Preferred Converter and one of the leading authorized suppliers of BISCO silicone foams in the USA. Full product line of Rogers BISCO silicones including HT-800 family of silicone foams.
• 3McoreTechnology or Integration3M Preferred Converter partner. Offers 3M pressure sensitive adhesives, conductive adhesives, and other 3M materials. Conducts adhesive lamination using 3M and Adchem products.
• Specialty Silicone Products (SSP)coreTechnology or IntegrationStrategic vendor partner for compression molding compounds and space grade silicone materials including SSP4716, SSP4734-50LV, SSP4734-70LV, and SSP4773 fluorosilicone. Partnership includes certifications of analysis and physical property test reports.
• LynxtercoreTechnology or IntegrationTechnology partner for S300X silicone 3D printing platform integration. This additive manufacturing technology enables printing with actual liquid silicone rubber formulations, reducing prototype validation timelines by a factor of six.

Scale indicators4 records

Recent moves7 records

Expansion highlights5 records

Broad incumbents

• 3M: 3M is a Preferred Converter partner supplying pressure sensitive adhesives, but also produces EMI shielding tapes, thermal interface materials, and specialty gasketing products directly. Its scale and direct OEM sales motion make it a broad incumbent competing for the same gasket and thermal management wallet.
• Trelleborg Sealing Solutions: Trelleborg is a global engineered polymer specialist with a large sealing solutions business producing custom elastomer seals, gaskets, and O-rings across aerospace, medical, and industrial end markets. It competes broadly with Stockwell's custom silicone gasket and seal offerings, particularly in aerospace and medical.
• Henkel (Bergquist): Henkel's Bergquist brand supplies thermal interface materials, gap fillers, and EMI shielding solutions for electronics. It overlaps directly with Stockwell's thermal gap filler pads, Condux conductive foam, and EMI gasket product families serving electronics OEMs.

Direct peers

• Greene Tweed: Greene Tweed is a custom engineered elastomer manufacturer serving aerospace, defense, semiconductor, and industrial markets with high-performance seals, gaskets, and polymer components. It directly competes with Stockwell in aerospace-grade and chemically resistant custom elastomer parts.
• Daemar: Daemar manufactures industrial sealing products including gaskets, O-rings, and oil seals across elastomer families. Its custom gasket and sealing product offering for industrial and electronics OEMs positions it as a direct peer to Stockwell's custom silicone gasketing business.
• Elasto Proxy: Elasto Proxy is a custom fabricator of rubber and silicone products including gaskets, seals, and vibration-dampening components for industrial, transportation, and electronics applications. It is a similarly sized niche converter competing in Stockwell's core custom silicone gasket market.
• Marco Rubber & Plastics: Marco Rubber is a custom fabricator of rubber and plastic sealing products including gaskets, O-rings, and molded elastomer parts for industrial, aerospace, and electronics customers. It is closely comparable to Stockwell's custom gasket and elastomeric component model.
• Parker Hannifin (Chomerics): Parker's Chomerics division is a leading manufacturer of EMI shielding gaskets, conductive elastomers, and thermal interface materials. It directly overlaps with Stockwell's EMI gasket, conductive elastomer, and thermal gap filler product lines serving electronics and defense customers.

Emerging players

• Rogers Corporation: Rogers is a key material supplier (BISCO silicone foams) and a strategic partner, but also produces engineered materials and EMI/thermal management products that overlap with Stockwell's downstream converter and custom gasket business. The dual supplier/competitor dynamic makes it a close comparable.
• Saint-Gobain (NORSEAL): Saint-Gobain produces NORSEAL silicone sponge and foam materials, supplied to Stockwell as a converter but also sold directly into sealing applications. The overlap in silicone sponge and foam gasketing makes it both a partner and a competitor.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights7 records

Customer concentration

• Xx.com/stockwellelasto
• Facebookfacebook.com/stockwellelastomerics
• LinkedInlinkedin.com/company/stockwell-elastomerics

Compliance19 records

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Stockwell Elastomerics