Designed to extend drilling reach, this 300mm extension bar is ideal for creating deep holes in cavity walls and thick masonry. It's compatible with the common 1/2" BSP thread size, featuring a male end for the drill and a female end for the core bit. The extension is made from hardened carbon and alloy steel for durability, and its solid construction provides a stable connection for efficient power transfer. It's a valuable tool for professional and DIY plumbing or electrical installations..