Abstract: A case is disclosed for protecting a collectible article, such as a baseball card, photograph, or the like. The article is enclosed within the protective case which comprises a base and a cover. Both the base and cover are preferably constructed from transparent elastic material, such as clear polyvinyl plastic. The base includes a peripheral boss which encircles the article when the article is placed on the base, and the cover includes a downturned edge which interlocks with the boss when the cover is applied to the base. Preferably, the boss of the base is angled outwardly, and the downturned edge of the cover is angled inwardly, so that the base and cover snap fit together due to the elasticity of the material used for constructing the base and cover, thereby sealing the article within the protective case. Preferably, a flange surrounds the boss of the base, and another flange surrounds the downturned edge of the cover, for increasing the rigidity of the protective case.