Australian Spa Parts - Spa plumbing pipe and tubing

Spa & Pool Plumbing Pipes, Hoses, Manifolds and Fittings

To assist in pipe sizes, the following list provides the physical measurements to identify the correct pipe size.

These measurements are of the EXTERNAL diameter of the pipe or hose (and spigot fittings, or internal diameter of socket fittings):

1/2" / 15mm            -  21.4mm               
3/4" / 20mm            -  26.8mm
1" / 25mm                 -  33.5mm
1.5" / 40mm             -  48.4mm
2" / 50mm                 -  60.5mm
2.5" (not 65mm)       -  73mm

These measurements are of the INTERNAL diameter of TUBING only:

3/8" / 9mm               -  9mm
3/4" / 19mm             -  19mm

External diameter of the barb fittings used with tubing is generally slightly larger than the bore of the tubing to ensure a tight fit.