MaximalPower Bronze Bore Brush 9&times;19mm Parabellum.357 Magnum / .38 Special .38 ACP (Auto) / .38 Super.357 SIG.380 ACP Caliber Firearms Great to remove what nylon bristles and cotton patches struggle with Brush Core Type: Aluminum. Brush Thread: 8-32 (Fits almost any rods or flex cables designed for cleaning) Bronze is strong enough to remove leading, but soft enough to not scratch steel bores Works in the following bores: 9x19mm Parabellum (9mm NATO) .357 S&W Magnum .38 S&W Special .357 SIG .380 ACP .38 ACP (.38 Auto) .38 Super And other 9mm/0.38" sized bores