Thomas & Betts LTTUS03B-K LFMC WTmp UL 3/4in Blk 150m/500ft

Metal core. The LTTUS03B-K uses a galvanized steel helical core with a black outer jacket, which is what makes it liquid tight flexible metallic conduit rather than nonmetallic. That steel core is what lets the assembly act as part of the raceway system when fittings are properly made up, and it is why you use steel liquid tight fittings rather than LFNC fittings on it.

Liquid tight flexible metallic conduit is built for exactly that: the black jacket over the galvanized steel core seals the run against water and oil, which is why it is the standard choice for outdoor motor whips, rooftop HVAC units, pump connections, and washdown areas. It also handles vibration at equipment terminations where rigid conduit would fatigue.

Pick the metallic type, like the 3/4 inch LTTUS03B-K, where the run takes physical abuse, needs crush resistance, or where you want the steel core in the assembly at a motor or compressor termination. Nonmetallic liquidtight is lighter and cheaper to pull, and it is the better answer where corrosion from chemicals is the main threat and mechanical damage is not. For a typical rooftop unit or motor whip subject to service traffic, the steel core version is the usual spec.

Order Thomas & Betts part number LTTUS03B-K. That designation covers the 3/4 inch black liquid tight flexible metallic conduit on the 500 foot (150 m) reel, and it is a single-configuration item, so there are no finish or length options to specify with it.