SealBoss 1570 Water Stop Foam mixed with 15x Accelerator is a flexible hydrophobic, water-activated (hydro-active), water cut-off grout and foam seal grout based on a MDI polyurethane. The resin is 100% solvent free and 100% solids. The gel-time of the product is adjustable by the mandatory adding of a certain percentage of 15x Accelerator. A phthalate free formulation (F) is available. 1510 WaterStopFoam is NSF/ANSI 61 Drinking Water Contact Approved. Upon contact with water 1570 Water Stop Foam reacts to a flexible foam while expanding its volume 30 to 40 times. The cured material is of a constant volume. Since water is not a component of the foam structure, the cured material is essentially not effected by water or dryness. The reacted material does not shrink or swell. Depending on the amount of accelerator added and the pressure of injection, 1570 Water Stop Foam reacts to a dense, closed cell, semi rigid material or a more open cell, semi flexible product. For best waterproofing results the closed cell structure is desired. 1570 Water Stop Foam is designed for sealing seeping water leaks and for cutting off water in cracks and joints. Due to the low viscosity of the material, 1570 Water Stop Foam offers superior penetration in hairline crack injection. The product is suitable for the filling of spaces, cracks and honeycombing in stone or concrete structures. To achieve most satisfying and permanent results in certain applications, a combination of 1570 Water Stop Foam with other systems of our product line may be advised. Ask your SealBoss technician for details. The product is for professional use.