The Protec Humidifier Cleaning Fish features a patented antimicrobial, Aquastat, that helps keeps your humidifier cleaner, longer. It helps kills up to 99% of odor causing bacteria. Simply drop in your humidifier tank for fresh, clean mist! Compatible With: Vicks humidifiers, Vornado humidifiers, Honeywell humidifiers, and humidifiers with tank openings larger than 1.6in/4cm•Scent: Unscented• Product Warning: Keep out of reach of children• Product Form: Capsule• Recommended Surface Application: Glass• Product Results: Cleaner• Recommended Product Application: Bath Tub