What do these magazines fit?

[Haris1]

Looks just like Grease gun mags but there is no mag catch in the back

 

[Tommyboy]

They look like 40 and 30 round mags for the MAC 10/45, likely produced by CMP for RPB. Here’s a picture of a ten rounder produced the same way with a Cobray stamp on the front. Not all had the Cobray stamp though. No mag catch like USGI Grease Gun mags because they were made to only be used with the MAC series of guns.

 

[Haris1]

Thanks a lot !!