The Leg Lock attachment works with the SCS-WB & FIDB Benches. Attaching to the end of the bench, it can be used as place to put your feet for a variety of exercises that require the added stability.The Leg Lock attachment works with the SCS-WB & FIDB Benches. Attaching to the end of the bench, it can be used as place to put your feet for a variety of exercises that require the added stability.