The Iron Age OP4D Oblio 4" Round Cast Iron Heel-Proof Drain Grate is a durable and high-quality fitting designed for industrial use. Made from cast ductile iron, it features a unique Oblio pattern that helps prevent debris buildup and ensures smooth drainage. With an actual outside diameter of approximately 4.50 inches and a nominal size of 4 inches, this round drain grate is a reliable choice for businesses and industrial applications requiring a sturdy and long-lasting solution for managing water flow.