This bit is used in specialized applications because of their ability for drilling and running wires through walls, ceilings and floors * Hitachi DuraCore treated products are manufactured utilizing a proprietary technologically superior to cryogenic treatment. * DuraCore is not a coating, so it will never wear off or chip away * Hitachi Black Gold drill bits stronger, sharper and last up to 300-Percent longer than standard Black Gold drill bits * Comes with a 30-day limited warranty