AR57 Ultralight Tactical AR-15 Upper Receiver Assembly 5.7x28mm 16″ Barrel M-LOK Handguard 50-Round Magazine

The AR57 Upper Receiver Assembly converts an AR-15 to shoot 5.7×28 FN ammunition. The unique upper design loads on top and accepts FN PS90 magazine (not included) and ejects downward through the AR-15 magwell. This upper is precision machined from a one piece aluminum forging. Forged from one 7075 T6 Mono bloc Aluminum, called a Kryptonite Mono bloc with a Black Melanite Treatment Finish.

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