EK-Loop Hard Tube is a solid type of extruded acrylic tubing intended for use with EK-HD push-in adapters and EK-HDC series compression fittings. The tubing may be heat treated to achieve certain bends. For expert users only! It is mandatory to chamfer the edges of the freshly cut tube in order to prevent gasket (O-ring) damage. EK recommends a 0,5mm x 45° chamfer.