Heat treated steel. Lower collars; steel. Low profile; allows +.060″ more valve spring travel. Simular to the OEM 80-84 collars that use guides with K-style stem seals.
Heat treated steel. Lower collars; steel. Low profile; allows +.060″ more valve spring travel. Simular to the OEM 80-84 collars that use guides with K-style stem seals.