BSI-Balance Systems is a company that has grown into one of the world s leading manufacturers of sash balances for single- and double-hung windows. The company was acquired by the Amesbury Group in 1995. BSI-Balance Systems maintains four manufacturing facilities, including two plants in Sioux Falls, S.D. It also has a distribution center in Ontario, Canada. The company offers a full line of window balances designs and can customize nearly any product. Its product lines include Block and Tackle and Constant Force Balances for wood, vinyl, aluminum and fiberglass windows.