Design: The clamp features a concealed thread that protects it from external influences such as sparks during welding, metal shavings in metal construction, or wood shavings and cement residues in wood and high-rise construction. The double-thread system accelerates the feed and allows for a very high clamping force. A brake under the sliding arm prevents unwanted slipping. By the way, the clamp can be placed horizontally on its back without tipping over.