What is the difference between TorqueMaster spring and torsion spring?

A standard torsion spring sits exposed on a metal shaft above the garage door, wound and unwound by hand using winding bars. A TorqueMaster spring, made by Wayne Dalton, sits sealed inside an enclosed steel tube on the same shaft, so it is hidden and contained. The functional difference is safety and serviceability. TorqueMaster springs cannot fly across the garage when they break because the tube holds them, but the cables and drums inside are lighter duty than a standard torsion setup. Replacement parts are proprietary to Wayne Dalton, and only certain installers stock them. Standard torsion uses universal parts available everywhere, costs less to service, and supports heavier doors better. TorqueMaster is safer to live with; standard torsion is easier and cheaper to fix.