New, opened box. iSonic F3900 is the most popular and the most effective ultrasonic denture cleaner on the market. AC powered, 110V 20W, 42,000 Hz true ultrasonic cleaner. Not a AA or AAA powered battery operated vibrator which is sometimes with false claims as ultrasonic but it's not ultrasonic at all. It's also the smallest ultrasonic denture/retainer cleaner on the market. Combined with iSonic White Ultrasonic Denture Cleaning Powder CSDW01, it is the Ultimate Denture Cleaning System for home use. It cleaned a 25-year old denture in 15 minutes. Try yours for 5 minutes? 5-minute auto shutoff. One button to push and easy to operate. It fits a pair of regular-sized upper and lower dentures, partials, retainers such as Invisalign, night guards, mouth guards, etc. For extra large pair of dentures or joined appliances, use model DS180. For multiple patients' dentures in a dental office, using model DS400B with a disposable PET cup is the best approach.