4" Diamond Plated Core Drill Bit (100 mm/4.02")

Hole Diameter: 4 in (100 mm) Core Diameter: 3-7/8 in (97 mm) Shank Diameter: 3/8 in (10 mm) Overall Length: 2-1/2 in (63.5 mm) Drilling Depth: 1-3/8 in (35 mm) Heavier and deeper layer of diamond coating and notches in the core allow to drill up to 200 holes in 1/4" thick glass. Diamond drills must always be used at a proper speed with suitable diamond coolant applied by spraying or submerging the contact area. Use of plain water will drastically reduce life of your drill. Diamond Tool Coolant is a Must for All Diamond Drilling. Recommended to use with our Diamond Tool Coolant to prevent overheating and prolong tool life. Use our Retaining Drilling Ring to keep the drilling area constantly submerged under the coolant.