This manifold downpipe system is for 1963-1967 Chevrolet Corvettes with 327 engine, 2 in. factory manifolds (Does Not Fit HP 2.5 in. Manifolds) and Manual Transmission (For Automatic Transmission use p/n 81096). These 2.25" mandrel bent pipes include factory style 3-bolt flanges, donut gaskets and a mounting system for an easy installation. Can be used with Flowmaster's crossmember-back kit # 817675 to create a complete system. Constructed in durable 409S Stainless Steel, the pipes are covered by Flowmaster's Lifetime Limited Warranty.