It is used for vertical and horizontal translation and rotation of loads. It acts as a "muscle multipliers". Manipulators counterbalance the weight of a load so that an operator lifts a small portion (1%) of the load's weight. It can be powered manually, electrically, or pneumatically. Manipulator's end-effectors can be equipped with mechanical grippers, vacuum grippers, electromechanical grippers, or other tooling. Manipulators fill the gap between hoists and industrial robots: they can be used for a wider range of positioning tasks than hoists and are more flexible than industrial robots due to their use of manual control. A manipulator is a device used under human control to manipulate materials without direct contact. The materials are frequently radioactive or biohazardous.