All camlock couplings 3/4”-6”have unified size standard. They can interchange. There is no standard for 8” camlock coupling. In general, there are two different sizes.
Type 1:
Inner diameter of male end(not hose tail) of camlock coupling is 231mm.
Inner diameter of female end(not hose tail) of camlock coupling is 231.8mm.
Type 2:
Inner diameter of male end(not hose tail) of camlock coupling is 226.8mm.
Inner diameter of female end(not hose tail) of hose supplier china's camlock coupling is 227.3mm.
They can not interchange. Now, most of USA clients use type 2 camlock coupling.
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