【 Parts that help improve machine performance and setup 】 These are popular 19mm diameter all-aluminum bearing rollers, now lighter. Weight has been reduced by approximately 30% in the aluminum portion due to six holes and shape modifications. The smooth rotation provided by the 520 ball bearings embedded in the roller body is also attractive. In addition to two rollers, two mounting screws and four aluminum spacers are also included. 【 Basic Specifications 】 2 x 19mm diameter all-aluminum rollers 【 Usable Machines 】 Mini 4WD PRO, Mini 4WD cars (Some bodies require modification) #Mini4WD #Roller #AluminumRoller #19mm