Aluminium Extension Bar for Cistern Levers 5/16" Square Drive - 9"
 
An aluminum extension bar for a cistern lever is 
an accessory used to extend the reachof a standard toilet flush handle, typically for use with concealed or hideaway cisterns. It provides a longer connection between the external handle and the internal flushing mechanism. 
Purpose and Function
The primary purpose of an aluminum extension bar is to bridge the distance in deep or hidden cistern installations, such as those within furniture, behind a wall, or where the user has difficulty reaching the standard handle due to mobility issues. 
Concealed Cisterns: Many modern bathrooms feature "concealed" or "hideaway" cisterns where only the flush handle or button is visible. A standard handle's internal arm would be too short to reach the syphon or flush valve, so the extension bar provides the necessary extra length.
Accessibility: For individuals with reduced mobility or physical constraints (e.g., using a toilet support frame), a standard lever can be difficult to operate. The extension bar can be adapted to extend the handle to a more convenient location or orientation.
Adjustability: The aluminum bar is often designed to be cut to the exact required length using a hacksaw, making it a versatile solution for various installation depths.
Connection: The extension bar often uses a standard square drive (like 5/16" or 8mm) to connect securely to the original lever shaft and the flush mechanism's internal arm, typically using grub screws for a firm fit. 
Material
The extension bar is commonly made from aluminum because it is lightweight and resistant to corrosion, an important factor given its use in a wet and humid toilet tank environment. This prevents the rust and degradation that can occur with other metal components over time.