Mapei have provided a Waterproofing flexible cementitious mortar for concrete surfaces subject to both positive and negative hydrostatic water pressure.
Waterproofing masonry structures and concrete, underground car parks, cellars, sunken swimming pools, basins, lift pits

The two compound mortar has high quality synthetic resin and the hardened layer is highly flexible and will remain stable under all environmental conditions

Liquid and Powder Kit is sold as one unit then you know the blend is of correct proportions

mapelastic foundation safety data sheet
mapelastic foundation data sheet