for Zebra ZQ520 Printer Battery:161% Longer Runtime with 6800mAh: One 6800mAh battery = 3 regular batteries,High-capacity lithium battery (vs. standard 2600mAh) powers 10+ hours in warehouses/retail stores – print 1000+ labels per charge! Battery for Zebra QLN320:Designed for Zebra printer battery:ZQ520, ZQ620, QLN320(HC), QLN220(HC),ZQ500,ZQ510,ZQ521,ZR628,ZR638,ZQ610,ZR658,ZR668,ZQ511,ZQ52 etc., 100% compatible with OEM specs. for Zebra ZQ620 Battery:5-Safety Protections & Zero Memory Effect: for zebra zq520 battery,Prevents overcharge, over-discharge, overheating, over-current, and short circuits. Certified safe for office/warehouse use.