Koster NB 1 Grey is a BBA Approved mineral based, sulphate resistant waterproofing system for positive and negative side waterproofing against pressurised water. It contains migratory crystallising and capillary-plugging agents. It can be used for waterproofing against ground moisture, and for non-pressurised and pressurised water. Waterproofing done with Koster NB 1 Grey is characterised by excellent resistance to pressure and abrasion as well as chemical and sulphate resistance.