New stock size SBT Powervalve, retaining screw and SBT leverlink. In the original design the pin had the ability to work itself free, sliding out of the top of the powervalve and allowing the valve to drop into the exhaust port. SBT leverlink surronds the pin, not allowing it to escape. A much needed upgrade to the original design. (Additional purchase of the 46-406 seal and gaskets is necessary)