Window frames move away from the siding or doors shift against the brick. They move when the temperature changes, the wind blows, or the ground swells. Big Stretch provides the adhesion and flexibility to handle the movement.Big Stretch is a 100% acrylic latex, high-performance caulk with powerful adhesion and elasticity. Big Stretch will stretch and compress to absorb just about any movement a home can dish out. It spans gaps up to 2" wide and stretches up to 500% of the original joint size without cracking.