Thomas & Betts LA150-15 1-1/2IN LTFLEX MTL COND STL 15M GRY

The PVC jacket over the steel core is what makes this conduit liquidtight, so it is the type used for wet and damp locations, rooftop equipment, pump and motor connections, and washdown areas. Standard non-jacketed steel flex (Greenfield) is dry-location only. You still have to terminate it with liquidtight fittings rated for the application, since the jacket alone does not seal the ends.

Treat it as needing a separate equipment grounding conductor. The core here is steel flex with a PVC jacket, and in the larger trade sizes liquidtight flexible metal conduit is generally not relied on as the sole ground path, so pull a green EGC sized to the circuit inside the 1-1/2 inch raceway.

Steel core, like the LA150-15, is the choice where the whip is exposed to physical abuse or needs to hold a bend shape against vibration, which is the usual motor, chiller, and rooftop-unit whip. Non-metallic liquidtight is lighter and cheaper but has no metal armor, so it is better suited to protected indoor runs and corrosive settings where no metal is wanted. Both are 1-1/2 inch trade size compatible with matching liquidtight connectors.

The LA150-15 jacket is grey, which is the standard color for general-purpose liquidtight flex on mechanical equipment, so it will read the same as most existing whips on a rooftop or mechanical room. If your facility color-codes raceways, note that this one is only offered in grey.