Unsure if it ever was actually used but can’t confirm 100% it wasn’t so. Regardless in VGC and has instructions. Fernox TF1 Total Filter 22mm The fernox tf1 filter is an ideal solution for removing any contaminants from your heating system and will connect to pipe with 22mm compression fittings The TF1 filter can be fitted vertically or horizontally and can be easily cleaned with out having to dimantle the filter.
eBay