size: 1/2", 3/4", 1", 1-1/4", 1-1/2", 2", 2-1/2", 3", 3-1/2", 4" ITEM NO. 6451~6460 material: Steel, fully threaded Indoor or outdoor. Use to connect two steel outlet boxes or other metal enclosures or to extend a length of threaded Rigid or IMC conduit. For more products catalog please contact our company.