Hot Racing Aluminum Disc Brake w/Calipers for Traxxas 4-Tec 2.0 (Red) (4)Hot Racing Traxxas 4 Tec 2. 0 Aluminum Disc Brake with Calipers. These optional disc brakes and calipers are intended for the Traxxas 4 Tec 2. 0. Using these will allow for increased scale looks and added durability. Package includes four aluminum hex discs, four calipers and hardware. Features: Perfect fit for the Traxxas 4 Tec 2. 0 Made from aluminum for a durable, scale look Larger front caliper and smaller rear caliper for increased scale accuracy