SB Tactical SBM4 Pistol Stabilizing Brace

The SB Tactical SBM4 is the simplest and least expensive way to put a stabilizing brace on an AR pistol. At 8.4 ounces and 7.2 inches, the SBM4 is a fixed-position, non-adjustable brace that slides directly over an AR pistol buffer tube measuring 1.1 to 1.25 inches in diameter. There is no carbine receiver extension, castle nut, or adjustment hardware to deal with; the brace clamps onto the tube and stays put.

The SBM4 evolved from SB Tactical's original SB15 arm cuff and uses the same forearm strap concept to stabilize the pistol. Because it does not telescope, it has fewer moving parts and a lower price than the adjustable SBA3, SBA4, or SBA5. At $44.99 against a $74.99 MSRP, the SBM4 is the budget anchor of the SB Tactical lineup.

The tradeoff for that simplicity is a single fixed length of pull and a non-adjustable cheek interface, so taller shooters or anyone running optics at varying heights will prefer an adjustable cuff brace. For a no-frills AR pistol where minimum cost and simplicity matter more than fit, the SBM4 is the default pick.