Depends on the basin but I normally do 100mm hole saw for countertop basin wastes as its just a stock holesaw I have. It's all covered anyway so who cares
Is it quartz or resin effect? Resin effect can be drilled with normal holesaws, Quartz I would be taking to a stone company
Is it quartz or resin effect? Resin effect can be drilled with normal holesaws, Quartz I would be taking to a stone company