This is the Pro-Line PRO-2 Pro Trac Axle Kit For the Traxxas 2WD Slash with Pro Trac Suspension Kit FEATURES: Made of steel. Lightweight outdrives for improved acceleration. Axle Snap Prings prevent drive pins from falling out. INCLUDES: Two dogbones Two axles Two outdrives Two snap rings Four M2x9.7mm drive pins Two couplings Two M3x3mm setscrews Two M3x1mm threaded pins SPECS: Dogbone, length: 87mm (3-1/2") shaft diameter: 3.8mm (1-11/16") Outdrives, length: 20mm (13/16") diameter: 11mm (7/16") Axles, length: 38mm (1-1/2") shaft diameter: 5.0mm (3/16") Couplers, length: 5.7mm (1/4") diameter: 4.7mm (3/16") Snap rings, diameter: 11mm (7/16") thickness: 3.2mm (1/8") COMMENTS: This set can be used with Pro-Line ProTrac Suspension Kit Slash 2WD (PROC6066) 12/17/12 phijwa ir/jxs