Torsion:

The use of force to twist or turn one end while the opposite end remains stationary.
* Bar: Long, made of metal, and used to shift torque from a spring to a winding plug
* Shaft: Shifts torque to a load from the springs
* Spring: A spring which is twisted in one direction on one end while being secured or twisted in the opposite direction on the other end in order to create torque.
* Spring Assembly: Parts constructing the counterbalance assembly.
* Spring Counterbalance Assembly: See Torsion Spring Assembly.
* Tube: See Torsion Shaft.
* Tube Coupler: Also called a coupler, this is used to connect one counterbalance shaft to another.