Extension bars, sometimes called 'extender arms', allow access to nuts that are difficult to reach, typically in automotive applications.

This Teng Tools extension bar has a 3/4 inch square drive. It is manufactured from chrome vanadium steel for strength and durability and has a satin finish.

The TENM340020 extension bar has the following specifications:
Drive: 3/4 inch.
Length: 100mm (4 inch).