An alternative to standard caulking compounds, flexible, compressible, Butyl Caulking Tape can be cut or shaped to fit practically any application. Uses include sealing deck hardware, including hatches, ventilators and more. Tough rubber, pressure sensitive mass, offers excellent adhesion to a variety of surfaces (no applicators required). Used to seal out: dirt, dust, moisture and water. Easy to use in tape form. Low moisture vapor transmission value. Tape is 1/8″ thick and comes in a roll 3/4″W x 20′ long.