This filter fits into the external housing and removes odour from the air which has been vented from the toilet waste tank. The SOG kits are supplied with a filter but this should be replaced once a year.
3M AP3 water filter head water filter head for HF10 cartridges
This head, complete with mounting bracket, has inlet and outlet ports so that you can connect it in-line upstream of your kitchen tap in your motorhome, caravan or boat. Accepts 3M's high performance HF10 cartridge for filtering down to 0.2 microns.