Markez® FFKM

An Advanced Material for Chemically Resistant, High Pressure & High Temperature O-Rings

Markez is a high performance perfluoroelastomer (FFKM) o-ring material that offers unmatched value for demanding sealing applications. Produced from nearly identical ingredients as higher priced brands, Markez compounds are used for high temperature o-rings, high pressure o-rings, and chemically resistant o-rings that deliver similar performance to major FFKM brands, with temperature resistance up to 625°F, at a significantly lower cost. Our proprietary processing allows us to supply seals under an inch in size more efficiently. Introduced exclusively to existing customers more than 15 years ago, we now have the experience and capacity to offer Markez high temperature o-rings and high pressure o-rings to the world.

Markez compound #Z1028 is our most popular general purpose FFKM due to its relatively low cost and broad range of chemical and temperature resistance up to 610°F (320°C). Popular sizes are available in stock with rush manufacturing options available. Used as an effective alternative to Kalrez® 6375, 4079, and 7075 in countless applications across various industries like petro-chem, paint, and ink where resistance to harsh solvents is required.

We welcome the opportunity to assist you in selecting the compound that provides the best value for your application. Our expert FFKM material engineers look forward to presenting the test data examples of why Markez offers the best value in the industry. Our Markez product line manager has more than 25 years of experience, including production and application engineering supporting worldwide brands to determine the best value product to perform in demanding applications.

Markez® high temperature resistant o-rings are in stock and available to buy online. Explore Markez® compounds and compatibility below or contact us for assistance in selecting the best material for the job.

Explore Markez Compounds

Compound #
Hardness (Shore A)
Comparable Compounds
High Temp °F (°C)
Low Temp °F (°C)
Strong Acids
Hot Amines
Steam < 300 °F
Steam > 550 °F
Explosive Decompression
USP Class VI Medical Grade
FDA Compliant
Improved Compression Set Resistance
Plasma Resistance
Oil and Gas
Chemical Processing
Life Sciences
Paint Spray Solvents
Alternative Fuels
Black 75 Kalrez® 6375 Kalrez® 4079 Kalrez® 7075
Best value general purpose performance, higher temperature resistance, wide chemical compatibility.
Black 75 Kalrez® 6375 Kalrez® 6230 Kalrez® LS205
Low cost performance value, nearly universal chemical compatibility, acid, amines, solvents, compression set resistance, FDA compliant and USP Class VI medical grade.
Black 75 Kalrez® 6375 Kalrez® 6380 Kalrez® 1050LF
General purpose, good in most acids, solvents, improved hot amine and steam resistance with wide range of chemical compatibility.
Black 75 Kalrez® 6375 Chemraz® 505
General purpose, good resistance to most paint solvents use in spraying applications.
Black 75 Kalrez® 6230 Kalrez® LS222
FDA compliant, higher temperature resistance, wide chemical compatibility. FDA compliant version of our flagship Z1028 compound.
Black 75 Kalrez® 7075 Kalrez® 4079 Kalrez® 8900
Highest temperature FFKM with best long term compression set resistance up to 335°C, short exposures up to 350°C, Low outgassing,high purity Wide range of chemical resistance, acid, solvent resistance.
Black 80 Chemraz® 615 Kalrez® 4079
Wider temperature resistance range, general purpose high temp material.
White 75 Chemraz® 513 Kalrez® 2037 Kalrez® 8575
General purpose white, good resistance to oxidation and high temperature exposure.
White 75 Kalrez® 6221 Kalrez® LS205 Chemraz® 625
USP Class VI and FDA compliant white FFKM with wide range compatibility.
Black 75 Kalrez® 0040
Improved low temperature resistance for use in oilfield and gas exploration, wide chemical resistance.
Black 90 Kalrez® 7090 Kalrez® 3018 Chemraz® 510
Higher temperature resistance Norsok M710 AED explosive decompression resistance, excellent resistance to Sour gas and associated chemicals and steam.
Black 90 Kalrez® 0040
Lower temperature resistance, AED explosive decompression resistance, providing the best overall temp range and Chemical resistance.
White 75 Kalrez® 7275 Kalrez® 8575 Kalrez® 9500
Improved plasma resistance, higher purity, wider temperature range, low extractables.
Violet 70 Kalrez® 9100 Kalrez® 8575 Kalrez® 9300
High purity, plasma resistant, high service life, semiconductor specialty compound.
Clear Amber 75 Kalrez® 9100
Higher purity clear translucent, semiconductor and laser grade material, excellent plasma resistance.
Clear Amber 62 Kalrez® 8002
Higher purity amber tinted clear, same as Markez Z1407 but lower durometer for lower compression force for delicate applications.

The information on this page is to the best of our knowledge accurate and reliable. However, Marco Rubber makes no warranty, expressed or implied, that parts manufactured from this material will perform satisfactorily in the customer's application. It's the customer's responsibility to evaluate parts prior to use.

The temperature ranges presented on this page are approximations for dry air service only and should not be used to determine design specifications or end-use temperature limits. Actual temperature range of a compound in an end-use application is highly dependent on part type, hardware configuration, applied forces, chemical media, pressure and thermal cycling effects, and other factors. The most practical way of determining an end-use temperature range is testing in the actual application conditions. Consult a Marco Engineer for more details.

Additional Material Information

Common Names

Perfluoroelastomers, FFKM

Trade Names

Chemraz®, Kalrez®, Markez®, Isolast®, Parofluor® , Perlast®.

General Description

Perfluoroelastomer (FFKM) is a highly fluorinated elastomeric family of compounds that provide the most resistance to chemicals and high temperature than any other elastomer in the market. FFKMs are considered the elastomeric equivalence to PTFE (Teflon) due to its excellent chemical and temperature resistance.

  • Excellent chemical resistance to most chemicals.
  • The highest temperature resistant elastomeric material in the market.
  • Can be molded into o-rings, X-rings and a wide variety of custom shapes.
  • Available in many different compound and colors targeted for specific applications and markets
  • Compounds available to meet FDA, USP Class VI and Explosive Decompression Resistance requirements.
  • Molten alkali metals
  • Dynamic applications
Temperature resistance

-46°C to 327°C / -51°F to 620°F (Compound and application dependent)

Have Questions About Your Specific Application?

Connect With an Expert
  • Expert product, application and design assistance
  • Trusted by 14,000+ customers
  • Fast response (usually within hours)