Electrical conduits and fittings are lengths of solid tubing used to house, protect, and cover electrical wiring and cables in power distribution systems. There are many standard conduit types. Flexible metal conduits (FMC) have a helically wound, circular raceway and are often used at the ends of rigid runs. Liquidtight flexible metal conduits (LFMC) have a sealed plastic covering over a flexible metal core. By contrast, liquidtight flexible nonmetallic conduits (LFNC) feature a liquidtight jacket over a flexible, nonmetallic core. Intermediate metal conduits (IMC) have rigid, circular raceways with thinner walls than rigid metal conduits (RMC). Galvanized rigid conduits (GRC) are made of metal and coated with zinc for increased resistance to abrasion and corrosion. Rigid nonmetallic conduits (RNC) are made of plastic and used in areas that are wet or corrosive. Nonmetallic underground conduits with connectors (NUCC) are somewhat flexible, corrosion-resistant devices with internal, factory-installed electrical conductors. Electrical metal tubing (EMT) conduits are relatively easy to bend, cut and form. Electrical nonmetallic tubing (ENT) conduits are circular and usually corrugated.