400+ bought in past month. Amazon with KUNPHY has the KUNPHY 46KHz Ultrasonic Jewelry Cleaner (12 oz) for $27 - 50% off with coupon code TITCXKKJ at final checkout = $13 with free shipping on $35+ or with Prime. Has 4.4/5 rating with over 1000+ Amazon reviews. 

Amazon promo codes don’t always work on the first attempt. Try refreshing the page and re-entering the code.