The 4" Octagonal Extension Ring Drain with a depth of 1-1/2" and no knockout from Southwire is a premium choice for electrical installations. Made from stainless steel, this extension ring offers exceptional resistance to corrosion and wear, ensuring longevity in various environments. Its octagonal design facilitates easy installation and secure fit, making it ideal for both residential and commercial applications. This product meets industry standards for safety and performance, providing electricians with a reliable solution for enhancing electrical systems without compromising on quality.