Bosch Multi head drill

Multi head drills are tools where the chuck is not permanently attached to the body and can be replaced by various other attachments to perform tasks that would be harder or impossible with a normal chuck.

Common attachments are a right angle attachment, to use the drill as an angle drill, an offset attachment that allows drilling and screwing in tight spaces, a 1/4" hex attachment for faster bit changes and a more compact machine.

Some multi-head drills allow a 1/4" hex bit to be inserted directly in the spindle without any attachments making the machine smaller and lighter than with a chuck.

The heads usually work with only one machine and are not compatible across different brands.

Black+Decker's Matrix Quick Connect system even has attachments for sanding, routing, sawing and other operations.