Athena Racing Cooper Ring cylinder head gasket. bmw m54 2,5 3.0 
For specific high horsepower applications, engine  performance can be significantly improved by using Athena Cooper Ring gaskets, that are supplied with INOX steel ring. This technology outperforms conventional fire ring solutions.
Cooper Rings are oversize (also fits for oversize bores).

for 84.00 84,25 84,5 85 pistons (recomendet)