ULTRAPLUG® hole plugs are designed to plug and seal unused holes in metallic, aluminum and nonmetallic enclosures. They fit a wide range of sizes – from ½” pilot light to 4” conduit trade sizes – so there is no need for restrictive hole-centering spacers. The self-centering, anti-rotational design ensures quick and simple one-person nut assembly and no tools are required for tightening and maintaining a NEMA 4X enclosure rating. Available in two colors.