What I have is a Rawlplug Durium Rotary Masonary Drill bit which has a screw thread. This attaches to a Rawlplug Durium/Vibroto Extension Sleeve which is
23cm long, Catalogue No 83-502. I have two of these.I can add as many extensions sleeves as I like as each extension sleeve has both a male and female end. Works with my normal B&D hammer drill. Purchased in the mid 70s.
Michael Chare