This is a optional XRAY Lightweight Hudy Spring Steel Drive Axle, and is intended for use with the XRAY T2 family of vehicles. This super lightweight drive axle for XRAY T2 vehicles, has been CNC machined from world renowned, top secret HUDY Spring Steel™. Strategically machined to reduce weight without compromising strength, this axle reduces rotating weight by up to 35% over the standard drive axle