This listing is for a set of (8) .215" High Domed Pistons and matching moly Ring set compatible with Big Block Chevy 454 in +.030" 4.280" Bore Diameter. Piston skirts are coated with 5/64" 5/64" 3/16" ring grooves, Pin diameter: .989", Press-fit pins only (included), For Stock 6.135" length rods & Stock 4.00" stroke. Good for street/strip or race/nitrous to 150 shot and RPM Range up to 7000. Stock 4.000" stroke. Press fit Pins.