The rubber seals around doors, windows and other panel openings serve an important function; they keep unwanted air and moisture out. However, as rubber ages it tends to dry out and harden, which often results in seals failing. Furthermore, this weathering also makes doors and windows prone to freezing shut during the winter months. 303 Rubber Seal Protectant helps to prevent these issues, as it restores and maintains the suppleness of rubber seals, enabling them to continue functioning like new. Its powerful conditioning action also restores the natural colour of seals if they have already faded. 303 Rubber Seal Protectant is very easy to apply, dries fully to the touch and does exactly what it promises to do. We love it!