Choosing the correct size E-Nano Water Adapter (GonG) is simple.

Measure the joint diameter on the water pipe where you would normally insert the “bowl” adapter. Standard sizes include 18mm/19mm or 14mm.

Alternatively you can purchase a SONG WPA instead which will accommodate any size from 14mm – 19mm.
XL E-Nano SONG – SEE PRODUCT HERE
E-Nano & NXT E-Nano SONG – SEE PRODUCT HERE