Developed by Huco, Vari Torque Couplings are small, user-adjustable torque limiters operated by friction using interleaved clutch plates. The clutches interrupt rotation when the load being transmitted reaches a pre-determined threshold. Rotation continues when the transmitted load drops below the threshold. They can be mounted in-line or concentrically and the various versions allow for different connections. They are used in all sorts of drives to protect personnel and equipment.