The Lisle spring clutch assures a proper fit on the piston and a positive locking action. Range: 3-1/2" to 7". Height: 7". Packaged in a box. Shipping weight: 1 lb. 11 oz. When installing pistons back into the cylinder bore, nothing works better than the right piston ring compressor. Eliminates risk of breaking piston rings and piston ring lands. Lisle's spring clutch eliminates any ratchet problems.