Camco TST MAX Orange RV Toilet Treatment Drop-Ins *10-Pack [41178]TST MAX Orange RV Toilet Treatment Drop Ins *10 Pack The TST MAX Drop Ins help control unwanted odors and break down waste and tissue in your black water holding tank. The easy to use drop ins contain a special chemical that helps break down waste, and a blend of orange scented surfactant oils that trap unwanted odors in your tank, making your camping experience more enjoyable. The drop ins are RV and marine approved, non formaldehyde and safe for all