Quantity of (2) Rolls: Grace #45639 Grace, 4" x 75', Vycor Deck Protector. Features a unique adhesive and membrane composition to provide corrosion protection, Prevents water infiltration at deck fasteners, Non-slip coating for easier foot traffic during installation, Compatible with all decking materials, Between the connector and pressure treated lumber and acts as a barrier layer to break the electrical circuit and helps reduce corrosion, Wraps around the roll.