Southwire type THHN or THWN 2 conductors are primarily used in conduit and cable trays for services, feeders and branch circuits in commercial or industrial applications as specified in the NEC 2. When used as type THHN or T90 conductor is suitable for use in dry locations at temperatures not to exceed 90 degree conductor is suitable for use in wet or dry locations at temperatures not to exceed 90 degree coolant. Red color.