The special ring found on the Martin Universal Airtight Watercolor Palette keeps your oils or acrylics fresh for days or even weeks. This palette is airtight, leak-proof, and seals in moisture. Numerous paint wells and dual 4- x 10-inch mixing trays keep your paints and inspiration as fresh as ever. About Martin Universal/F. Weber Co. For a century and a half, the name Martin Universal and F. Weber Co. have been synonymous with quality art materials. Established in 1853 in Philadelphia, Pa., the Martin/Weber is the oldest and one of the largest manufacturers of art materials in the United States. * Airtight, leak-proof palette * Multiple wells for storing and mixing paint * Two 4- by 10-inch mixing trays * No assembly required * Folded dimensions: 10.5W x 5D x 1H inches