Front Lower Control Arm Bumper (31064) by Dorman®. Quantity: 1 per Pack. Damaged shock absorbers and/or springs can add far too much shaking, rattling and rolling to any ride. Now you can ensure a smooth journey with Dorman’s durable Control Arm Bumper. Weather-resistant for a long life, the bumper is made of high-quality rubber or polystyrene foam to absorb heavy impact. It helps prevent damage to the control arm, frame, shock mounts, and other suspension parts. It also provides a substantial cushion when your car bottoms out over bumps.