Materials
Grade cross-reference
If you are switching from an established perfluoroelastomer grade, start here. Each pairing below is drawn from publicly published hardness, temperature and compression-set figures, with the reasoning shown so you can judge it yourself.
Please read first — The pairings below are a parameter-level comparison drawn from publicly published hardness, service-temperature and compression-set figures. They are provided to help you shortlist grades for evaluation — they are not an equivalence claim. Sealing performance depends on the actual media, temperature, pressure, motion and gland design. Always validate with a sample and your own test protocol before switching an approved part.
| Our grade | Comparable grade | Their hardness | Their range | Their comp. set | Basis for the pairing |
|---|---|---|---|---|---|
| OMS70S | Kalrez® 6375 | 75 Shore A | −20 to +275 °C | 24 % | Closest match on hardness and upper temperature; broad-spectrum chemical resistance for semiconductor service. |
| OMS70S | Chemraz® 505 | 75 Shore A | −30 to +230 °C | 25 % | Comparable hardness and chemical breadth, but a lower upper temperature limit. |
| OMS7102 | Kalrez® 4079 | 75 Shore A | −19 to +316 °C | 14 % | Same hardness class; their published compression set is tighter and upper temperature higher. Compare on cost and lead time. |
| OMS7102 | Isolast® J9677 | 75 Shore A | −10 to +300 °C | — | Closest match on the service temperature range and static-only duty. |
| OME7505 | Kalrez® 7075 | 75 Shore A | −18 to +327 °C | 10 % | Same hardness class and thermal-process duty. Their upper limit is marginally higher and compression set substantially tighter. |
| OME7505 | Chemraz® 615 | 80 Shore A | −18 to +324 °C | — | Similar thermal-process range at a slightly higher durometer. |
| OME7505 | Perlast® G75TX | 75 Shore A | up to +325 °C | — | Comparable high-temperature black FFKM for thermal oxidation and diffusion. |
| OMS7503 | Chemraz® 605 | 80 Shore A | −20 to +260 °C | 22 % | Comparable dry-etch duty. Lower durometer here, but a materially better published compression set. |
| OM7502 | Chemraz® 505 | 75 Shore A | −30 to +230 °C | 25 % | Same hardness and wet-chemical duty; their lower temperature floor is deeper. |
| OM7502 | Chemraz® 585 | 85 Shore A | −20 to +260 °C | — | Comparable wet-process chemical resistance at a higher durometer. |
| OM7542 | Kalrez® 0040 | 70 Shore A | −42 to +220 °C | — | Matching −42 °C lower limit. Higher durometer here; their upper limit is slightly lower. |
| OM7542 | Chemraz® 564 | 80 Shore A | −40 to +230 °C | — | Comparable low-temperature wet-media service. |
| OM7542 | Chemraz® 678 | 90 Shore A | −40 to +230 °C | — | Comparable low-temperature range at a much higher durometer — relevant if rapid gas decompression is a concern. |
| OM9090 | Kalrez® 7090 | 90 Shore A | −26 to +325 °C | — | Matching durometer for high-pressure gas service; their upper limit is higher. |
| OM9090 | Kalrez® 0090 | 95 Shore A | −27 to +250 °C | — | Slightly higher durometer, commonly specified for rapid gas decompression duty. |
| OM9090 | Chemraz® 510 | 90 Shore A | −30 to +230 °C | — | Matching durometer; lower upper temperature limit. |
Our grades at a glance
| Grade | Hardness | Service temp. | Comp. set | Test condition | Process | Seal type | View grade |
|---|---|---|---|---|---|---|---|
| OMS70S | 73 Shore A | -10 to +275 °C | 23 % | 70 h @ 250 °C, 25 % deflection, Type B | Dry + Wet | Static + Dynamic | |
| OMS7102 | 75 Shore A | -10 to +300 °C | 20 % | 70 h @ 250 °C, 25 % deflection, Type B | Dry + Wet | Static | |
| OME7505 | 75 Shore A | -10 to +320 °C | 23 % | 70 h @ 300 °C, 25 % deflection, Type B | Dry + Wet | Static + Dynamic | |
| OMS7503 | 70 Shore A | -10 to +275 °C | 17 % | 70 h @ 200 °C, 25 % deflection, Type B | Dry | Static + Dynamic | |
| OM7502 | 75 Shore A | -10 to +230 °C | 19.6 % | 70 h @ 200 °C, 25 % deflection, Type B | Dry | Static + Dynamic | |
| OM7542 | 75 Shore A | -42 to +230 °C | 19.6 % | 70 h @ 200 °C, 25 % deflection, Type B | Wet | Static + Dynamic | |
| OM9090 | 90 Shore A | -10 to +290 °C | 16 % | 70 h @ 200 °C, 25 % deflection, Type B | Dry + Wet | Static + Dynamic |
Brands referenced on this page
All of the above are trademarks of their respective owners. They are referenced for material-selection comparison only. No equivalence, endorsement, sponsorship or affiliation is implied.
How to validate a switch
- Compare the service temperature, not the headline number. A grade tested at 300 °C is not a grade tested at 200 °C.
- Check compression set at your actual temperature and duration.
- Confirm durometer against your gland design — higher hardness is not always better for extrusion-critical service.
- Request a sample and run it in your own test protocol before releasing to production.
Send us the incumbent part
The fastest route to a confident quote is the part you are replacing — or its part number. We will reverse-engineer the geometry, identify the closest grade and flag any parameter that needs your engineering review.
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