Mondur MRS 4 is a low to medium functionality polymeric diphenylmethane-diisocyanate (pMDI) with a moderately high 2,4 -MDI isomer content. Mondur MRS 4 has utility in binders, elastomers and other applications where its technical properties provide benefits. It offers balanced reactivity for formulations while maintaining moderate viscosity. Mondur MRS 4 can be used to develop products with improved mechanical strength, adhesion and durability suitable for various end uses.