All, Well L96 users, we don`t need to buy a Japanese made Hop up unit for your cheap rifle anymore!!! HP made a re-designed hop up chamber for all of us. All brass construction, with a steel lever for adjust hop up. Drop in fit, no modification required!! Design for use with TM compatible Hop up bucking and Inner barrel, Original hop up bucking and barrel can no longer be used. The metal ring for adjust hop up should be used with, check HP website for instruction.