Markez Z40 FFKM O-Ring: Compound, Equivalents, UK Suppliers
Verified by Rachel Mayfield, Supply Chain Analyst - April 2026
Markez Z40 is a 75 Shore A perfluoroelastomer (FFKM) manufactured by Marco Rubber. It seals continuously to 316°C and is specified for steam service and similar service. Steam/amine-resistant FFKM.
Specifications
| Property | Value |
|---|---|
| Compound | Z40 |
| Manufacturer | Marco Rubber |
| Maximum continuous temperature | 316°C |
| Minimum temperature | 0°C |
| Hardness | 75 Shore A |
| Colour | Black |
| Material family | Steam/amine-resistant FFKM |
Where Markez Z40 is used
Markez Z40 is specified for: Steam service, hot amines.
Markez Z40 equivalents from other FFKM manufacturers
If Markez Z40 isn't available, these compounds from competing manufacturers have similar chemistry and operating windows. Always verify against your actual fluid and temperature before substitution.
| Equivalent compound | Manufacturer | Max temp | Hardness | Direct match |
|---|---|---|---|---|
| Kalrez 4079 | DuPont (Chemours) | 316°C | 75 Shore A | ✓ |
Available O-ring sizes
Markez Z40 is supplied in:
- BS 1806 sizes: BS001 to BS932 (UK / EU standard, imperial-origin metric)
- AS568 sizes: -001 to -932 (US standard, dimensionally identical to BS 1806)
- ISO 3601 sizes: metric IDs from 2 mm to 670 mm with cross-sections 1.0 mm to 7.0 mm
- JIS B 2401: P, G, S series (Japanese OEM equipment)
- Custom / non-standard: built-to-print for OEM applications
For a list of sizes commonly stocked in the UK, see the BS 1806 size chart, ISO 3601 metric chart, or contact a UK seal specialist below.
UK availability
Markez Z40 is supplied in the UK by FFKM specialists carrying multiple manufacturer lines. Lead time is typically 2-5 working days for stock sizes, 4-8 weeks for custom-moulded sizes. Use the form below to get a quote from a UK FFKM specialist.
References
- Marco Rubber — Manufacturer
- ISO 3601 O-ring sizes
- BS 1806
Frequently Asked Questions
What is Markez Z40 used for?
Markez Z40 is a 75 Shore A FFKM (perfluoroelastomer) compound from Marco Rubber. It is used in Steam service, hot amines. Continuous service temperature: 0°C to 316°C.
What is the temperature rating of Markez Z40?
Markez Z40 has a continuous service temperature range of 0°C to 316°C. Short-term excursions above the maximum are possible but degrade service life.
What is the equivalent of Markez Z40?
Direct equivalents to Markez Z40 include: Kalrez 4079. Always confirm chemical compatibility against your specific fluid before substitution.
How much does Markez Z40 cost?
FFKM O-rings such as Markez Z40 are typically £30 to £500 per piece depending on size, with custom or large-bore parts at the upper end. Get a current quote via the form on this page.
Where can I buy Markez Z40 in the UK?
Markez Z40 is supplied in the UK by independent FFKM seal specialists with multi-brand inventory. Lead time is 2-5 working days for stock BS/AS568 sizes, 4-8 weeks for custom-moulded sizes.
References
- Marco Rubber — Manufacturer
- ISO 3601 O-ring sizes
- BS 1806