Block and tackle balance system

A balance system holds the sash in place in any position. The block and tackle balance is a type of balance that uses both a block and tackle (a pulley system with a high-density nylon pulley and a moveable block) and a heavy duty spring within a rigid channel to counterbalance the weight of the sash and hold it in any desired position. The tension from the spring creates resistance that, combined with the pulley system, allows for the smooth opening and closing of the window.

A block and tackle balance system is easy and relatively inexpensive to install and replace, and it improves the structural integrity of the window.