ARP 1942001 Intake Manifold Bolt Kit, Black Chrome Moly Steel With Hex Style Heads, For Select Pontiac Applications Facilitates optimum sealing of gasket surfaces to prevent intake manifold leaks Manufactured from chrome moly steel with a black oxide finish Rated at 170,000 PSI, which is considerably stronger than Grade 8 hardware Precision rolled threads prevent galling while promoting more consistent torque loading Heads are conventional hex style, and washers are included