Traxxas TRX-4M Aluminum/Brass Bead-lock Wheels with Adjustable Offset. Constructed from high quality CNC-machined brass with adjustable offsets, these optional aluminum and brass wheels are intended for the TRX-4M micro crawler to add a total of 140g of weight to help lower the CG of the vehicle for enhanced crawling performance, increase the durability and add bling to you TRX-4M! Get these stylish heavy wheels and give your TRX-4M the boost it needs in style and performance!