Bill that would be a SMLE mag I assume, I don't think any 375's were build on that action type all on the MLM MLE Long Tom action & mag set up, quite different ?

I have a 375Ex & 2 mags + a 8mm Lee Speed, but not with me right now, I must go get the 375Ex to check the mag for you guys, but from memory looks the same to me other than being shorter & squared off, same ever where else.... I think !