... Core Drill Bit for Construction 1. good quality 2. huge selection 3. factory directly 4. core bit for concrete, etc ... 38358601.57408601.97508602.17558602.36608602.76708602.9575860core bit for concreteOuter DiameterWorking Length (mm)inch"mm0.8"203601 ... used for cutting, grinding or polishing stones, refractory, porcelain, glass, concrete, asphalt etc. Diamond Core Drill Bit for Construction