Need help identifying mags

[MSFoster]

A friend of mine found a cache of what appear to be milsurp mags with no markings whatsoever any help identifying these would greatly appreciated.

 

[ronny]

Probably M1 Carbine .30 cal., 15 rd mags.

 

[MSFoster]

That's what I thought I've got a buddy with one I'm gonna take it to him Monday and see.

 

[doorgunner]

Yup, M1 carbine.

 

[AKguy1985]

M1 carbine

 

[Sniper John]

Yep, X4