Primus DM is a dry mix, polymer-modified, cementitious adhesive and base coat. It is supplied in 23 kg. (50 lb.) bags and, when mixed with water at the job site, produces a high performance, easily applied adhesive and base coat for use with Dryvit® systems. Primus DM is used to adhere expanded polystyrene insulation board to acceptable substrates and to embed Dryvit reinforcing mesh as part of the base coat for Dryvit systems and is required in Dryvit non-combustible (NC) systems.