Cho-Seal® and Cho-Sil® EMI-Shielded O-rings & Chomerics Conductive Gaskets

CHO-Seal 1285, CHO-Seal 1287 EMI shielded O-rings

CHO-Seal and CHO-Sil EMI shielded conductive elastomer O-rings and gaskets are made of silicone, fluorosilicone, EPDM or fluorocarbon-fluorosilicone binders with fillers of pure silver, silver-plated copper, silver-plated aIuminum, silver-plated nickel, silver-plated glass, nickel-plated graphite or unplated graphite particles.

Chomerics CHO-Seal and CHO-Sil conductive elastomers and EMI shielding products feature excellent EMI shielding and resistance to compression set over wide temperature ranges. Chomerics EMI shielding conductive O-rings meet MIL-STD-810 requirements for fungus resistance, and EMI shielding O-rings and gasket compounds also act as environmental and pressure seals.

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CHO-Seal EMI shielded O-rings and extrusions are for military and commercial applications, and excel in aerospace applications. Specialty shielded conductive elastomers are also available for low-closure force, waveguide and corrosive environments.

Conductive EMI shielding seals are available as extruded elastomers, can be cut to length, and are available in profiles including: hollow and solid D; hollow or solid O; hollow P and rectangular, as well as many other shapes. Conductive profiles can be ordered with pressure-sensitive adhesives (PSAs) applied.

Co-extruded EMI shielding strips (combo gaskets) provide optimal EMI shielding and corrosion protection. When conductive and non-conductive EMI elastomers are vulcanized together, they create a technically superior design for aircraft doors, rack mounted cabinetry, and military and commercial communications.

Filler and Binder
CHO-Seal L1285
silver-plated aluminum in silicone
90-110 dB
Military gasket of choice for corrosive environments, lightweight, 392°F (200°C) max. use temp, good EMP resistance, molded, extruded.
CHO-Seal 1287
fluorosilicone version
CHO-Seal 1298
silver-plated aluminum
90-110 dB
Material of choice for aircraft and marine military applications, high performance in harshest corrosive environments, good physical properties, molded, extruded. Best corrosion resistance.
CHO-Seal S6304, S6305,6370
nickel-coated graphite in silicone
>100 dB
Good performance in moderately corrosive environments, good for flange finishes needing "bite-through" for electrical contact, flame retardant. 6370 is UL 94V-0 rated.
CHO-Seal L6303
fluorosilicone version

CHO-Seal 1298 gaskets available as molded, die-cut and extruded seals. CHO-Seal 1298 offers resistance to fluids and fuels used in aviation and industrial applications.


Standard Extrusions - Various shapes and types of Chomerics extruded conductive elastomers: solid O strips, hollow O strips, mushroom D strips, solid D strips, hollow D strips, hollow P strips, V strips and channel strips.