Using natures biocide, Tea Tree Oil, Gel-clear green strips kill airborne and waterborne microbes, leaving a fresh pleasant smell.Gel-clear Green Condensate drain strips are a natural solution using natures biocide. It is a purpose developed condensate drain strip for wall mounts, continuously releasing Tea Tree Oil molecules.Effective for 6 months, Gel-clear Green condensate drain strips are a natural approach to blocked condensate case drains. Preventing biofilm and foul odours from the drain pan.Gel-clear Green is safe and simple to use leaving a fresh, pleasant fragrance for its entire lifespan.