Sport Ridge AR15/M16 5.56 Chamber Brush. Precision threads ensure tight and reliable rod connection. Powder residue in the chamber can cause corrosion and affect barrel life and accuracy. Specifications for Sport Ridge Chamber Brush: Manufacturer: Sport Ridge Caliber: 5.56x45mm NATO Length: 5 in Additional Features: Chamber Brush Weight: 0.75 oz Gun Model: M16 AR-15 Width: 1.5 in Package Contents: Sport Ridge Chamber Brush What firearm models does the manufacturer say Sport Ridge Chamber Brush is compatible with? The manufacturer suggests that Sport Ridge Chamber Brush is compatible with AR-15 M16Sport Ridge 03970B: AR15/M16 5.56 Chamber Brush