a device for drawing or braking metal bands or metal sheets and including two oppositely arranged endless revolving chain systems with a gap therebetween through which a metal band or a metal sheet is displaced and including carriage - like roller blocks for effecting one of clamping and driving the one of a metal band and a metal sheet , an elastic lining for covering the roller blocks ; a plurality of shaping and filler pieces for controlling tension applied to the elastic lining ; and elements for generating magnetic fields for controlling driving and / or restraining forces applied to the metal band or the metal sheet .