For pre 2004 models this is an alternative twin gas cylinder connection system which uses your existing regulator.
It is designed for the low pressure side of your gas system after your regulator. The two supply inlets controlled by a two way tap and can use either type of LP gas – one side can be propane and the other butane.
Switch 2 makes changeover easy and allows the empty cylinder to be removed without switching off the supply. It is supplied with 3 hose clips and is fitted with a mounting bracket.