Sparco side mounts are used to mount competition seats. Side mounts have mutliple side holes that provide a customizable mounting position. The Aluminum HD side mounts have an added benefit of being able to mount in either direction with the legs facing in or out giving you more vehicle mounting options. The HD side mounts are larger than the standard Aluminum Side Mount. All aluminum construction available in anodized silver only. Includes Qty-4 8x1.25 bolts (side mount to seat).