CMMG is a gun manufacturer making AR-15’s in many different calibers: one of them being 22LR. They also have their own 22LR AR compatible magazines. There used to be different models of CMMG 22LR magazines but nowadays only one model is available.

Information regarding the discontinued CMMG magazine models is sparsely available and this article would not be without RifleMags.co.uk. Kudos to them for having this information posted online.