Electroplated Diamond core drill bit 1.Diameter:4-120MM 2.Diamond grit:40# 60# 80# 120# Electroplated Diamond core drill bit 1.Diameter:4-120MM2.Diamond grit:40# 60# 80# 120#3. Features: smooth drilling surface, high drilling speed, long service life, no broken edges, and not tremors.4. Application: the product uses electroplating Diamond technology, suitable for hard materials, such as glass, ...