... 120T SWL Worm Screw Elevator Description:Screw lift, SWL series worm gear screw jack lift is a basic component, ... support, high reliability, long life. 1, structure type Lift divided by structure type: Type 1 - same as ... 4, two types of transmission gear ratio than the lift, that isnormal (P) and slow (M). 5 ... , the protective screw screw lift the protective type 1 is divided into: basic, ...