G2 Ergonomics 40-150 - Billet Throttle Tube Best engineered aluminum throttle tube on the planet! Machined from 6061 aluminum in the USA! Delrin bushings prevent aluminum-to-aluminum contact - buttery smooth action!! Changeable "cams" (sold separately) allow ratio change - Quicker?? More control?? No problem!! Removeable end cap for easy handguard or Jimmy Twister bearing installation.