Replaceable Tendon for iBase. The most innovative tendon when it comes to performance and safety. Instead of the usual polyurethane material we use a BASF high-tech material for the connecting string, which is about 50% tougher and more durable. Another advantage of this exclusive tendon material is that it avoids the usual offset between rig and board slowing you down. That‘s why the iTENDON is the first choice of many PWA competitors as it offers a more direct power transmission between rig and board than any other tendon out there.