Spectre's Intake Bolt and Washer Set is engineered to provide premium quality hardware for Chevrolet 265-400 and Chrysler 273-440 small block engines. Measuring 3/8 inch-16 by 1 inch, these grade 5 bolts feature a corrosion resistant zinc-plated finish and hex heads to ensure easy installation. This kit includes 12 bolts and washers.