Spidertrax Ultimate 40 spline Inner Gun Drilled Axle Shaft Assembly - Single 6-38 (Sa/Sb are Measured in Inches from Center of U-Joint to End of Shaft)  Spline Detail: 40 Spline Inner Axle Shaft 24/48 Pitch 45 Pressure Angle Class 6/7 Fillet Root

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.