A2Z Ozone A7K Ozone Generator Remote Control for timer and fan settings Single or dual plate activation for 3500mg or 7000mg ozone output Repeat timer setting for 30 minute, 1 hour, 2 hour or 4 hours Stainless steel handle for easy portability from room to room Ideal for basements, large areas, offices and hotels Voltage: 110V US 30 Minutes to an hour 1 - 2 hours 3 - 4 hours