USB Cup Warmer - USB Coffee Mug Warmer This USB Powered Warmer can keep your beverage, coffee or tea hot all morning long. Take power directly from your laptop, PC or Mac Keep beverage, coffee or tea warm at 122-140 F USB powered, no batteries needed. Easy installation, no driver required, plug & play. Rated power: 2.5W - 5V DC. With On/Off switch. Red LED indication when warmer is turned on. Plug & Play, without driver installation, easy to carry around to be used anytime and anywhere.Brand new, 1 year warranty!