SWL Worm Screw Elevator 1.in line with JB/T8809-1998 (original JB/ZQ4391- ... .Carrying capacity of the 2.5-120T SWL Worm Screw Elevator Description:Screw lift, SWL series worm gear screw jack lift ... , low noise, easy to install, flexible, multi-function, multi-format support, high reliability, long life. 1, structure type Lift divided by ...