While I received the Sterra as promised, that is where the "customer service" ended! It was too big for my space but when I attempted to contact customer service for return instructions, it was impossibly challenging! NO response and NO phone contact but ample message that there was a strict time limit for return with credit! Returned to address on invoice in the carton only to learn that that was not the correct address for returns. Fortunately, my shipping agency IS CUSTOMER SERVICE friendly and contacted me. I have now returned the Sterra to your preferred but difficult to find address! Have now paid shipping TWICE! You probably have a very good device but the customer service is dismal!!