Dewalt tile drill bits 5 25mm dewalt dt6046 qz this set of drill bits from dewalt has been designed to perform the task of easy and accurate drilling of holes in glass slate granite and tiles including porcelain tiles up to grade 5 manufactured with safety in mind the central core created during drilling stops the drill from wandering while the core can be removed easily through the core ejection slot dewalt dt6046 qz tile drill bits set of 5 5 6 7 8 10mm water delivery system