Desmophen 670 is a slightly branched, hydroxyl-bearing polyester resin suitable for use as a co-reactant in the formulation of flexible, weather-stable coatings. As a high viscosity resin, Desmophen 670 when combined with common polyisocyanates like Desmodur® R N 75A and Desmodur® N 3390A results in films with excellent low-temperature flexibility and very good weather stability ideal for applications requiring durability against environmental elements. Desmophen 670 can also be used as a flexibilizer in other two component polyurethane coating systems. Combining the benefits of flexibility and weather resistance, Desmophen 670 is a versatile additive for products subjected to varying temperatures and weather conditions.