High performance chromium - faced aluminium piston fits for Honda CB250 JADE250 Bore:48.5mm(STD) Weigh: 150 g Piston kit: Pins, pin fitment, lock and rings High performance aluminium piston features: 1.Chromium aluminum alloy meets or exceeds OEM specifications, 2.CNC-machine to extremely close tolerances 3. Pistons supplied in a kit package that includes rings, wrist pins and circlips. 4. Pistons offered standard and big bore pistons feature specifically engineered for extreme applications, including professional competition. 5.The ultimate durability and longevity for standard riders in most applications. 6.The dome piston dish and smooth flowing radii requires no deburring or preparation.