Froth-Pak 620. Tank B-Polyol, part 2 of a kit of 3. Froth-Pak foam sealant is a two-component, quick-cure polyurethane foam that fills cavities, penetrations, cracks and expansion joints. Froth-Pak foam sealant can also be used as a sealant and void fill in many foofing applications. Unlike one-component foam, which uses moinsture as a curing agent. Froth-Pak is a chemically cured foam, significantly reducing curing time. Froth-Pak dispenses, expands and becomes tack-free in seconds. The product will skin over in 30-40 seconds and will be completely cured in minutes. Must be used with BMR code 038-3727 and 038-3745. Covers 620 square feet when vaporizing 1" thickness. The more you vaporize thick the more you diminish the dimensions in square feet. The calculation is done by a rule of 3. BMR code 038-3736 (resin). BMR code 038-3727 (catalyseur).