Malleable cast iron screw clamps are built to a very high quality with a unique rail and firm iron arm. Impressive anti-slip technology, made from tough durable materials, the arms are cast iron while the 25 x 6mm rail and spindle are both optimised for smooth running and slip free usage.Clamping force up to 500kg. High-quality 2-component plastic handle and pressure plates can be replaced by hand. With protective caps on the clamping surfaces. Stable profiled rail with serration.