Amazon.com: Hard Bendable Flame-Retardant Opaque Blue Nylon Tubing for Air and Water Applications - Inner Diameter 0.167" - Outer Diameter 1/4" - 100 ft : Industrial & Scientific
0.170" ID x 1/4" OD Blue High Pressure Flexible Nylon 12 Tubing | U.S. Plastic Corp.
Amazon.com: .250" ID x 3/8" OD Blue Nylon High Pressure Flexible Tubing (100 FT) : Industrial & Scientific