ADA STYLE , 4-PORT CYLINDER, 2-IN-1 ROUND SHINNY DOME STYLE COMBUSTION CHAMBER, NEW BILLET HEAD DESIGN WITH REPLACEMENT BILLET CAPS, EXHAUST PORTING, BARREL HAS AN EXTRA BOOST PORT MACHINED INTO IT, 44mm PISTON HAS A DOUBLE WINDOW PORT, 14:1 COMPRESSION RATIO, FULL SET OF GASKETS, CIRCLE CRANK IS ALL STEEL CONSTRUCTION, MADE BY IN HOUSE CNC MACHINED, VERY NOTICEABLE TORQUE AND TOP END GAINS, *piston is for 10mm wrist pin.