Pro-Shot 50 Caliber / 12.7mm Chamber Brush Brass. Like bore brushes Pro-Shot's chamber brush is also made to last with a brass core looped end and bronze bristles. Specifications for Pro-Shot 50 Caliber / 12.7mm Chamber Brush: Manufacturer: Pro-Shot Color: Brass Features of Pro-Shot 50 Caliber / 12.7mm Chamber Brush Stiff Bronze Steel Bristles-Tapered Bristles to provide excellent cleaning of case neck area Excellent for the removal of heavy fouling Precision American Standard #8-32 threads Package Contents: Pro-Shot 50 Caliber / 12.7mm Chamber Brush Pro-Shot 50CH: 50 Caliber / 12.7mm Chamber Brush Brass