This invention is directed to a sulfur-containing composition that can be used as golf items such as golf ball components and golf equipments. The sulfur-containing composition comprises the reaction product of four reactable components: (a) polyisocyanates and polyisothiocyanates; (b) polyols and polythiols; (c) epoxides and episulfides; and (d) amines and anilines; at least one of the four reactable components contains a sulfur atom. This invention also relates to a reaction injection molding process, a castable molding process and other methods using the sulfur-containing composition.