Overall Length: 12"Optimized For Drilling Diameters From 1-1/2" To 5", But Can Accommodate Up To 6" If The Brush Ring Is RemovedDust Port Can Be Hooked Up To 1-3/8" Vacuum Hose Nozzle Or 1-1/4" And 2" Nozzles When Combined With An Appropriate Adapter (Included)Dual Air Chambers Provide For Both Dust Collection During Use And Provide Suction To The WallRubber Seal Maintains Suction On The Drilling Surface