About This Size-----Diameter 7.2mm; total length 117.5mm; diamond height 74mm; diamond grit #40/45; round shank Application-----Very useful for mortar raking and brick removal, removing old mortar prior to repointing or removing blown, damaged bricks or natural stone Vacuum Brazing Technology-----High-quality diamond raw materials and vacuum brazing technology provides faster removal work and longer service life Best Choice-----It is better suited and easier to use on intricate and delicate work, particularly vertical joints and natural stone jobs Recommended Machine-----Corded Drill, Cordless Drill, Benchtop Drill. Use electric hand drill: Recommended speed: 2000-5000RPM; Faster the RPM, longer the drill bit's working life. When use Angle Grinder, please install angle grinder drill chuck Overview Material : Diamond Cutting Diameter : 7.2 Millimeters Finish Type : Diamond Shank Type : Round Brand : FOCSTOL