The Zebra ZQ520 and ZQ521 are rugged mobile direct thermal printers designed for field and industrial use. They support Android, iOS, and Windows Mobile with Bluetooth 4.1, WiFi 802.11ac, NFC tap-to-pair, and USB connectivity. Built for durability, they are IP54 rated, MIL-STD 810G certified, survive 2m drops, and 1300 tumbles. They feature a 3250 mAh rechargeable Li-ion battery with smart power management and sleep mode. The printers support barcode, text, and graphic printing, gap/black mark sensing, XML, built-in fonts, and web management tools. The ZQ521 is the newer updated version of the ZQ520.