... L600mm,Dia34mm U head size: 160*105*30*5mm Adjustable length: 400mmProduct advantages : 1. The scaffolding U head ... . The extension of scaffolding u head jack is adjustable from 30mm to 40mm for different building heights.4 ... steel beam and plywood on it.5. With high durability and strength,u head jack provides stable ... ,tunnel,bridge and subways. Product photos: High quality Adjustable scaffolding u head