All round-end stock tanks have an extra-heavy-duty, molded rim and an extra-deep sidewall rib design for additional strength One-piece molded design resists abuse. New heavy duty, molded-in aluminum drain fitting and 1¼" poly drain plug ensure a longer life than ever before. Tested to -20° F, corrosion-free, impact resistant and recyclable. UV protected. Three-Year Manufacturer Warranty. Blue.