Internal Diameter: 8.4mm Outer Diameter: 3/8 inch (approx. 9.5 mm)
Assembly Instructions:
Best to use a plumbing cleaner then pipe cement to assemble. Be sure you do not glue over the air hole of your manifold as it is easy to web the glue when using on a small area.
Additional Notes:
Used mainly as a air pipe to take air from the manifold to the jets in the Spa. Often also used for the Ozone venturi.