A blow molded product which is generally tubular having a first and second open ends, a bellows section intermediate said first and second ends so that the product is flexible, and a skirt adjacent the second end, the skirt having an outer cylindrical outer surface and a lobed inner surface is provided. The bellows section is formed in a blow molding operation and the skirt is formed by injection molding. The final product is formed by thermally fusing the two portions together thereby forming a product with a substantially cylindrical external surface and a non-cylindrical internal surface which has lobes or other internal projections.