Product reference: 7151X. The U-joint pins are held in place by a heavy duty O-ring so you never have to worry about losing a pin. The nickel plated steel shafts and black oxide treated accents not only look good, they are designed to exacting specifications for ultimate strength and performance.Accessory part for these models:1/16 E-Revo® VXL1/16 E-Revo® VXL: TQi™ Traxxas Link™ Enabled 2.4GHz Radio & TSM® (Model# 71076-3)1/16 E-Revo®1/16 E-Revo®: TQ™ 2.4GHz radio, Titan® 550 motor (Model# 71054-1).