Bihui Core Bit Set of 5 with Two Milling Bits

The BIHUI diamond core bit set includes 5 core bits of 25, 35, 40, 45 and 68 mm + a tapered finger bit 20-48 mm and a straight 20 mm finger bit. The core bits have a diamond layer made by the newest method: the diamonds are bonded to the bit by vacuum brazing. This method lets you drill holes very quickly and with no effort even in hard porcelain stoneware. Drilling is best done at medium speed on the angle grinder. Before drilling it is worth putting a wet pad inside the bit, cut to fit the bit beforehand. Start the hole and drill while constantly changing the angle from side to side. Do not press hard against the surface of the tile. On no account cool it down suddenly. Do not drill a run of holes one after another, let the bit rest. The gem of the set is a good case for storing the bits. A medium-diameter bit, in 10 mm porcelain stoneware on average, should do 40 to 50 holes. No warranty