HydroQuip 26-C3548-1-7T-K Heater, LowFlow, D-1 Tri-Bend, 2.1/3.4kW, 115/230vLaing Triple Bend Low Flow Replacement Heater by Hydro Quip Replacement low flow tri-bend style heater assembly with 3/4 inch barb fittings, and built-in Manual Reset TCO (thermal cutoff). OEM part number C3548-1. This is a trombone style heater that replaces similar style Laing low flow tri-bend heaters. The heater is rated at 3.4kW/230v, and 2.1kW/115v. The internal low density heater element is made of titanium metal. It provides the best heat to water transfer. This type of heater is typically found in many Dimension One Spas (D1), Reflections Spa Model. This heater comes with 4 electrical wires with terminal ends. A flow switch (sold separately) is normally installed with this heater.