... (LS2 / LS3 / LS6 / L92 ) Professional Flap Top:(standard Bore:4.000" and 4.065". Rings:1.2mm ... . 1.115, -5cc Dome Vol, 4032 alloyFlat Top,4.030''Bore, Rod lgth 6.125", Comp ... . 1.115, -5cc Dome Vol, 4032 alloyFlat Top,4.005''Bore, Rod lgth 6.125", Comp ... . 1.315, -5cc Dome Vol, 4032 alloyFlat Top,4.060''Bore, Rod lgth 6.125", Comp ... alloy LS (LS2 / LS3 / LS6 / L92 ) Forged Piston-Professional Flap Top-