SBB-2 Sure Stop stopping devices for 2-inch track, designed specifically for hi-lift and vertical lift applications. Sold as a pair. These handle doors up to 2,200 pounds, which is a serious capacity jump over the standard-lift version. When a cable snaps on a heavy vertical-lift or hi-lift door, the door can come down fast and hard. The Sure Stop engages the track and catches the door before it drops. At 2,200-pound capacity, these are meant for commercial and industrial doors. Confirm your track size is 2 inches and your lift type is hi-lift or vertical before ordering.