1,double drum wind. 2,applicable for free fall punching and piling 3,mainly use in construction site ... in construction site, factory, mine, port, especially suitable for free fall punching & piling for bridge, dock, construction works and so on.This winch ... without electric power. Pls see below detailed technical date for different models:Model2JKL82JKL5Wire rope rated pull KN8050Wire rope rated speed ...