Who is M-Cor Inc. ?

M-Cor, Incorporated, founded in 1987, is a family-owned corporation. Our corporate office is located in Bensenville, Illinois, USA, near Chicago’s O’Hare Airport. M-COR’s manufacturing facility is located just east of the picturesque Rocky Mountain front in Helena, Montana, USA, only an hour away from Yellowstone National Park.

M-COR manufactures high-performance encapsulated o-rings and extruded products for a wide range of applications and industries. In 1987, our principal product was FEP and PFA encapsulated o-rings. Two years later we added encapsulated cam and groove gaskets to our product line. Within five years the growth of our company made it necessary to increase our manufacturing capacity. Thus in 1992 we opened a manufacturing plant in Montana, USA. Our new facility enabled us to double our production capacity to meet customer demands.

Throughout the 1990s M-COR continued to grow its customer base. With the emergence of globalization, we recognized an opportunity to expand our product line and market outreach. So in 2002 we added new equipment and technologies to extrude high-performance elastomers, including FKM/FPM (Viton®), silicone and EPDM o-ring cords and extrusions. In 2003 M-Cor Inc. was included in DuPont Performance Elastomers Genuine Viton® Program. In 2006 our engineering department developed a breakthrough technology, an  encapsulated manufacturing industry first —curing technology for the manufacture of continuous extruded lengths of Viton® GFS and Viton® Extreme ETP elastomers for conversion into high-performance encapsulated o-rings and various sealing devices for use in severe environments.

Thus, by 2007 our high-performance sealing product line included Teflon encapsulated o-rings, Teflon encapsulated gaskets for cam and groove couplers, precision and ultra-high-precision o-ring cord extrusions, complex profiles and tubing extrusions of Viton®, silicone and EPDM.

A further expansion of our technical resources arrived in 2012 with the introduction to our manufacturing facility of on-site CNC machining, 3D computer-aided design (CAD), computer-aided machining (CAM), laser-measurement technologies, and 3D printing for prototype tooling. These innovations have enabled us both to control tooling costs and to expand greatly our capabilities to design and machine complex Teflon encapsulated o-ring molds and extrusion dies.

With these capacities in place, M-COR is uniquely positioned to meet even the most stringent engineering requirements for prototyping and mass production of encapsulated o-rings and gaskets.

Now, in 2015, we are introducing micro-diameter encapsulated o-rings with inside diameters as small as .207″ (5.28 mm)!

M-COR will celebrate 30 years of serving the sealing industry in 2017. Our success can be attributed to the opportunities our customers have offered us to serve their needs, their continued confidence in our products and services, and the dedication of our staff of employees.

New products are always on the horizon, so please visit our website often for updates!


Larry Mattera
General Manager


Rick Mattera
Engineering DIrector


Ray Mattera
Accounting Manager