Renpho via Amazon offers the Renpho 300ml Smart WiFi Essential Oil Diffuser for $28.99. Coupon code "24FVDO7Q" cuts it to $23.19. With free shipping, that's $4 under our January mention and at least $12 under what most third-party sellers charge via eBay. It works with Alexa and features 7-color LED mood lighting and an adjustable mist output. Deal ends April 22.