I wanted to follow up on my post about spare o-rings for the Nibbler XL. I never got a response from G so I went ahead and ordered both 904 and 906 type siicone o-rings.
It turns out that the '906' o-rings are a perfect match. The o-ring in the picture sitting on top of the paper label is the original that came with the Nibber XL. The '904's are too small to fit the Nibbler XL mouthpiece. So, anyone who has a Nibbler XL water tool and wants to pick up some spare o-rings these are the ones to get:
906 S70 Silicone Rubber O-rings
Hedo