Quick Answer
ECO provides a cost/performance pathway for fuel/oil and low-permeability applications; FKM occupies a premium tier for high temperature and aggressive chemical/fuel sealing.
ECO vs FKM: practical comparison
| Selection factor | ECO | FKM |
|---|---|---|
| Fuel resistance | Strong | Excellent in many fuel systems |
| Permeability | Low | Low to very low depending grade |
| Temperature range | Moderate specialty range | Generally higher |
| Cost | Lower | Higher |
| Typical role | Fuel hose, vapor, seals | Premium fuel/chemical/high-temp seals |
How to choose
Use ECO where required performance can be achieved without the premium temperature/chemical capability of FKM. Use FKM where service severity demands it.
Important: Ratings describe general polymer-family tendencies. Exact performance can change materially with grade, formulation, cure system, fluid composition, temperature and test method.
Frequently asked questions
Only after application testing. Cost reduction is meaningful only if ECO meets all temperature, fluid and service-life requirements.
Both can be strong; ozone usually is not the deciding factor between ECO and FKM.