Abstract: A molded polyurethane foam system utilizing hydrofluorocarbons and alkane hydrocarbons as the blowing agent. The molded polyurethane foam products of the invention have a high-density integral skin and a low-density core. The blowing agent can be the HFC, tetrafluoroethane (HFC-134a) chemical alone or a mixture of tetrafluoroethane (HFC-134a) with one or more of the following: alkanes (such as 2-methylbutane, pentane and heptane) and other inert volatile organic compounds with boiling points in the 15.degree.-100.degree. C. range (such as pentene and acetone).

Abstract: A baseball bat comprising a hollow metal core of varying diameter and a foam plastic body enveloping the core. The plastic body has a handle section and a hitting section that are separately molded so that said handle section is softer than said hitting section and can be of a different color when desired.