I have compared crimp rings and fittings for both Vanguard and Zurn. The Vanguard crimp rings are a little wider and a bit thicker than Zurns rings. The fittings look to be the same. Can you use a Zurn crimper on a Vanguard crimp ring as long as you use a Vanguard go/no go gage? The Vanguard crimpers are more expensive.