MULTILAYER PIPE CLAMPS Heavy series Tube clamps are consist of Top plates, Bottom weld plates, Hex bolts, Plastic or aluminium Jaws. PP – Plastic Polypropylene –dark green colour approved as per DIN 3015 standards worldwide. Heavy Series Tube Clamps are available in ready stock from 6 mm od till 219 mm od of Tubes in PP PA Aluminium types raw materials.