... equipment 1. CE and ISO certificated. 2. Stable and safety lifting and lowering 3. Single mast,6-13.8m heigh Aerial ... to span common ground bars.----Lifting chain load safety factor more than 10:1,also have steel wire safety protect systerm,make ... fix,it is very convenient to work.----light-duty,single series high altitude work flat roof, electrohydraulic transmission,safety and credibility ...