The 3/8 in thru 1-1/4 in WARDFLEX® tubing is terminated using the patented, STEPSAVER double seal fitting. The 1-1/2 in and 2 in tubing utilize the WARDFLEX® traditional gasketed fitting design. Only fittings designed and listed for use with the WARDFLEX® and WARDFLEX® MAX CSST Piping Systems shall be used when connecting to the flexible piping.