This listing is for a Pack of 1 Following drilling the essex flange allows for fitting without the need to gain access to the back of the flange Provides a 22mm compression connection on a flat or curved surface such as the side or top wall of a copper cylinder for connection of any 22mm pipe work This immersion heater flange comes with rubber sealing washers and brass washers. This cylinder flange has a no stop connection which allows the pipe work to extend through the flange as much or little as possible into the cylinder, Manufacturer: Primaflow