Thanks as well asked garage & they did not know what it was for.
Just got our first Land Rover 05 Free Lander 2 L D HSE found same just swinging & not fixed could this filter touch any thing hot exhaust turbo & be fire hazard ? & Why would a solenoid valve VENT need a filter & not just exhaust to atmosphere what would symptoms be if filter was blocked when it cannot be seen, also thee is a upside down U shaped pipe with no connection to it in the same area as the filter at the drivers side back of the engine ?