Gears & Gear Drives manufactures worm gear screw jacks/linear actuators for precise positioning which are used primarily for lifting or lowering masses in both vertical and horizontal planes. The weight to be lifted varies from 0.5 tonnes to 150 tonnes. These units offer positive mechanical action, and fail proof, precise positioning. The height to be lifted [or] lowered can be up to 3,000 mm. There are two standard speeds available, viz, normal lift and slow lift, approximately 0.5 mm and 1.5 mm rise of screw shaft per rotation of the input worm shaft. There are two types of worm gear screw jacks lifting screw rod with the stationary head and rotating screw rod and moving nut. Two further design possibilities are design A [upward] and design B [downward]. These can be used on sideways or angular ways also. Accessories such as anti run device, additional safety nut, wear monitoring unit, telescopic lifting screws, and additional accessories such as miter gearbox, bellows, and protective pipes are available. The areas of application are paper machinery, material handling equipment, industrial automation, cement machinery, satellite communication equipments, process machinery like food industry, welding, etc.