Check the listing for details. HVAC Commercial Diffuser LCD PCB Programmable Scenting 3500-7500 sf. Color: As Pictures Showing, Condition: New, Made in China. Listed at 239.40 USD. STRONG and SOLID - aluminum alloy shell that is heavy, Sleek, slender look for any room in the home or office. NO WATER NEEDED - unique system making this machine water free allowing better scenting coverage. POWERFUL LONG-LASTING DIFFUSER: This essential oil diffuser is powerful easily filling a space with fragrance. HVAC Capable - multiple type uses, including pieces to hook it up directly to vent system HVAC. QUIET: The noise from our diffuser is under 42dB so will effectively blend with the ambient noises in your surroundings, creating a unique and inviting ambiance in your home. PCB DISPLAY - set your concentration, hours and days timing digitally with the touch screen PCB.