Classes A, B, C, D, G, and M. 1  Classes A â C permit operation of motor vehicles based on GVW rating and must be renewed every 5 years. 2  Classes D and G are valid for operation of a single motor vehicle with a GVW rating of 26,000 lbs. or less.
Electrical Metallic Tubing (EMT) Electrical metallic tubing (EMT), also commonly called thin-wall, is a listed steel raceway of circular cross section, which is unthreaded, and nominally 10â² long. 20â² lengths are also available. Covered by Article 358 of the NEC, EMT is available in trade sizes 1/2 through 4.
Contact Our Conduit Division. Western Tube & Conduit Corporation is the leading producer of steel tubing, both black and galvanized, for all of the western United States. Additionally, they are one of the leading major national conduit manufacturers. Conduit is essentially a tube or trough that is used for protecting electric wiring.