Answer 19: First of all, we always recommend you to use our original fittings, as the matching between our hose and fittings is guaranteed. However, in case you have no choice but to use the fittings produced by other manufacturers, our recommendation is that a fitting outer diameter size should be about 5-15 % bigger than a hose inner diameter size. For instance, if you look for a suitable fitting for I.D. 12mm hose, the recommended outer diameter size of fittings should be between 12.6mm and 13.8mm. Please note that the recommended fitting outer diameter size varies, depending on the hose material (such as PVC, Nylon and Fluorine). If you are not sure about the appropriate selection of the fittings, please consult with us here. We are happy to guide you an appropriate solution.
