Traxxas 4-Tec 2.0/3.0 Aluminum Rear Suspension Mounts. These optional mounts will help you dial in the suspension on your Traxxas 4-Tec 2.0 and 4-Tec 3.0. Inserts are used to adjust anti-squat and rear toe angle. Package includes two blue mounts, six inserts, twelve hinge pin retainers and eight hallow balls.