Republic HRC501 single-stage side channel blower with IE3 premium efficiency 3.4 HP, 50/60 Hz, 1-phase, TEFC (IP54) motor. Standard features include heavy duty aluminum construction, cool-running outboard bearings for long life, integrated inlet and discharge silencers for quiet operation, 2" NPT inlet and discharge connections, and a cUL, UL, and CE listed motor with class F insulation. An inlet filter and relief valve are strongly recommended and sold separately. Fully assembled packages with inlet filter, relief valve, gauge, and even sound enclosures are also available.