Dress up your Buick 231 V-6 engine with this 202-Piece stainless steel hex head bolt kit. This kit is guaranteed to fit! The kit includes the proper flat washers to insure that your Oil Pan, Valve Covers, Etc. get the proper support that is essential for a good, long lasting seal. The kit also includes .062 thick stainless AN MIL SPEC washers where they belong. These washers are a close tolerance reduced size washer that fit in the tightest spots. Included in the kit are the following component kits: Intake Manifold, Oil Pan, Thermostat Housing, Distributor, Fuel Pump, Water Pump/Timing Cover, Coil Braket, Carb Stud Kit, Header Bolts (Allen Head) , Crank Pulley, Fan Pulley, and Valve Covers. If you need any bolt substitutions for aluminum valve covers or any other non-stock parts on your engine, please email or call us and we will gladly substitute them for you. We recommend using anti-seize at all thread points.