The mounting material is an advanced microcellular urethane with open-cell construction for exceptional energy absorption and resilience that acts as a pressure reducer and shock absorber for flexographic plates. R/bak materials let printers improve registration, reduce dot gain, decrease plate deformation, maintain ink density, and use finer screens for finer line work. R/bak S-plate cushions and carriers come in two hardnesses: R/bak SF (firm) and R/bak SS (soft). The general-purpose R/bak U cushion can be cut, shaped, and mounted to even the smallest diameter cylinder.