The tubes are made from TPR (Thermoplastic Rubber) which then has a soft nylon outer sleeve that covers the whole of the tube. The reason for this is that in the unlikely event that should the inner TPR tube break or snap whilst exercising, the nylon sleeve will restrict the amount of movement so to avoid any potential injury that the snapping of a tube may cause.
All 66fit safety exercise tubes are 1.4m in length and have detachable metal clip handles. This enables the user to add an extra 66fit safety tube should they feel the need to increase the amount of resistance required. There are 5 different resistive strengths in the range starting from a level 1 going up to level 5.