PU form Spray polyurethane foam that expands to three times its original volume on contact with air. The expanding action fills holes, cracks and gaps more completely than standard caulks. Density, lbs./ft.3 ASTM D 1622 1.3-1.8 Compression Strength, psi ASTM D 1621 11 Tensile Strength, psi ASTM D 1623 33 Shear Strength, psi ASTM C 273 18 Shear Strain, psi ASTM C 273 57 Closed Cell Content, % AS ...