OX-ON Filter set Comfort A2 is a safety approved organic vapour filter for you, who need to protect your airways in connection with working with paints, varnishes and solvents - including cellulose thinners, various types of wood preservatives, pesticides, turpentine. PCB and spray paint. (You may read more under point 8 in the data sheet for the product, against which you need to protect yourself). The filter set is with screw thread, which makes it extremely easy and quickly for you to mount. The OX-ON Filter box w/4 sets Comfort A2 consists of 4 sets of filters, which are used in conjunction with your OX-ON half mask.