Melonmold Square Watermelon Mold for Making Cubed Watermelons Square Shaped Watermelon Mold used for shaping a standard watermelon that you can grown in your personal garden (No special seeds required). This mold is constructed out of non-toxic Polycarbonate plastic. Included with the mold are all the nuts and bolts needed to properly seal the mold. All parts are designed for outdoor use and will last many growing seasons to ensure you get the most out of your mold.