Beretta BRX1 Magazine Adapter This polymer magazine adapter allows the use of MAGPUL LR-SR model magazines (in .308 caliber) with a .308 caliber BRX1. The adapter is only compatible with Magpul LR/SR magazines. The magazine is NOT included with the adapter, must be purchased separately, and CANNOT be purchased on the Beretta website. Compatibilities:BRX1 Style number: C5J795