The malleable cast iron screw clamp is made of high-quality material and is therefore very robust and durable. The malleable cast iron clamping arms have flat contact surfaces that allow clamped workpieces to be set down securely. The ribbed edges of the arms ensure secure locking and prevent slipping or automatic loosening. The galvanized profile rail of the clamp is ribbed on both sides and ensures a secure hold. The galvanized spindle with trapezoidal thread enables optimum power transmission.