Sashco 10016 Caulk, White,-30 to 250 deg F, 10.5 oz, Cartridge

Big Stretch® is a high-performance water-based elastomeric sealant with powerful adhesion and excellent elasticity. It spans gaps up to 2 in wide and stretches up to 500% of original joint size without cracking. Big Stretch won't crack, it just stretches.