ferongr wrote:

Got the 17mm ID x 1.5mm o-rings and they were really a bit too thick. Ordered 17mm x 1mm o-rings from Ebay (FT doesn't have them) and those fit just perfect.

I found these here at FT and they do have an ID of 17mm:

19*17*1mm (OD*ID*T) SKU 2167600

OTOH I already had these 17*15*1.0mm (OD*ID*W) SKU 2066601 and although they are not the size you mentioned, they do fit much better than the original. Like you said an ID of 17mm would be perfect.

BTW thanks for your useful input.