The new Core Drill Adapter from Stihl mounts on the existing wood drill on the Stihl BT 45 and converts it into a gasoline-powered, handheld core drill for drilling holes in concrete. Standard adapters fit a wide range of manufacturers' core bits and accessories. The water valve on the adapter adjusts to apply the right amount of water to cool the bit and flush the hole. The water attachment comes standard with a 5/8 in. adapter for core bits up to 1-1/2in. in diameter while an optional 1-1/4 in. adapter is available for mounting larger core bits from 1-5/8 in. up to 6 in.