REAL AVID BORE MAX SPEED BRUSH MULTI-CAL PACK FEATURES: This Bore-Max Speed Brush pack includes 10 popular pistol and rifle calibers in one convenient storage case. Bore-Max Speed Brushes have twice the bristle density of standard brushes for maximum scrubbing power and faster results. Stiff, nickel-plated phosphor bronze bristles reduce chemical breakdown from solvents and extend the life of the brush.