ST Racing Concepts Heat Treated Steel universal driveshaft set for Slash 2WD Carrying over design and material selection from our HPI Blitz and Associated SC10 universal kits, our Slash 2wd universal kits features large diameter universal driveshaft bone for more durability against the power of today's Lipo battery/Brushless motor combo, the heavier weight of short course truck, and larger diameter of short course truck tires. We also used the same carbon steel material for axles, which features two sets of universal pin holes so you can get twice the life out of the same set of axles. The universal joints and joint pins are of carbon steel material as well and the pins features a "step" for the setscrew to have a flat spot to more securely hold the universal driveshafts together. Lastly, even the universal shaft roll pin at the end was not over looked. Carbon steel at the pin although strong will unfortunately add excessive wear to the diff outdrives, thus a different material was selected just for the shaft pin for durability and ease of wear on the diff outdrives.