New Old Stock (NOS) V-Twin Manufacturing Big Bore Piston Kit This is a standard size Big Bore piston kit for Harley-Davidson Twin Cam engines. It is designed to increase displacement from 88" to 95" when used with 3-7/8 bore cylinders. The outer box is rough from storage, but the internal components are in like-new, unused condition. Kit Includes: Pistons, rings, wrist pins, and clips. OEM Reference: Replaces Harley-Davidson part # 22661-99A.