The rack with integrated crankshaft is protected of deformation. Without big complexity you crank your working platform even on complex underground into level. The two rack wheels made of high- tensile malleable cast iron are attached loosly to the hexagonal shaft. This makes a canting nearly impossible, allows a smooth operation and makes the Scaffold Trestle nearly maintenance free. The Scaffold Trestles B-S and B-SK have removable base which saves space while transporting and storing. The permissible load per Scaffold Trestle is 14.0 kN (1.4 t).