Made of 40Cr Carbon Steel, stronger than the original gear, wear-resistance and better transmission. The upgraded 40Cr Carbon steel Spur Gear 33T M1.5 and large gear shaft, bearing and aluminum 7075 fixed mount bring out three-point support, which is better than the original two-point support in stability and transmission effect. Motor tooth diameter: 5mm, D-shaped motor gear hole, Module: 1.5mm, Number of teeth: 13T, Tooth surface width: 9mm. Spur Gear 33T diameter: 6mm, D-shaped motor gear hole, Module: 1.5mm, Number of teeth: 33T, Tooth surface width: 14mm, Outer diameter: 52.4mm. Package includes : Motor gear 13T-1pc ; 4x5 Screw shaft-1pc ; Spur gear 33T M1.5-1pc ; Cush drive input shaft-1pc ; Bearing 6x13x5-1pc ; shim 6x8x3.5-1pc ; shim 6x8x7.5-1pc ; Set Screws 5x5-1pc ; Aluminum 7075 mount-1pc. Suitable models : Traxxas 1/5 X-Maxx 6S 77076-4, X-Maxx 8S 77086-4, XRT 8S 78086-4.