The Keeney K836-22 Anti-Condensation Toilet Tank Liner Insulation Kit helps prevent water from forming on the outside of a toilet tank by creating a barrier between the warm outside air and cold water inside the tank. Ideal for houses with water temperature fluctuations such as those with well water that create condensation buildup on the toilet tank wall, the closed cell foam liner prevents the buildup of water droplets in order to keep floors dry and prevent water damage. Simply drain your toilet and dry the inside walls before cutting the 16-inch x 48-inch liner to fit the shape of your bowl and peel the adhesive backing.