This listing is for a set of eight (8) +.020" over size 4.020" Bore diameter Dish top pistons and a Moly piston ring set (Hastings/Perfect Circle/MAHLE) compatible replacements for Mercruiser 5.7L V-8 Dish Top Hypereutectic pistons. 255hp 260hp 270hp 280hp 300hp MIE Mag Alpha Engines. Piston specifications are as follows: BORE: 4.020" (at .020") HEAD TYPE: Recessed head - we carry flat top pistons in other listings RING LANDS: 5/64"-5/64"-3/16" COMP. DISTANCE: 1.540" PIN DIAMETER: .9275"