This is a replacement cylinder & piston for the OS .40LA engine. / / Features: This is a matched set (cannot purchase the parts individually). / / This is an "ABC" cylinder & piston set."A"luminum piston,"B"rass / cylinder liner, with a "C"hrome plating on the cylinder. / / The plating is actually Nickel but is still being labled ABC not ABN. / / The inside of the liner is tapered so when the piston goes up it gets / tighter. . / / This has 4-ports and an alignment notch for proper installation. . / / Includes: 1 matched cylinder and piston only, piston pin is NOT is included. / / Specifications: Bore: .8346" (21.2mm) Stroke .734" / 10-23-97 JBR