FEATURES:-Fits most centerfire & bolt-action rifles-Protects chamber & bore from damage-Aligns rod w/ barrel for faster cleaning-Reduces solvent leakage into actionPRODUCT SPECIFICATIONS:Dimension 1.40 X 4.00 X 15.10Height 1.4000Width 4.0000Length 15.1000TYPE BORE GUIDESCALIBER OR GAUGE NOT APPLICABLEMATERIAL NOT APPLICABLEMASTER PACK 1OTHER FEATURES: INCLUDES A COLLAR FOR MSR FOR TIGHTER FIT & ADDITIONAL SUPPORT OF THE UPPER RECEIVER THUMBSCREW COLLAR LOCK FOR SECURING BOLT INTO POSITION