Model Number: WH-E34 thermal printer Brand Name: WH,Brightek Key Specifications/Special Features: Please refer to the table below ItemsSpecifications Printing method Direct thermal line printing Paper width 57mm Print width 48mm Resolution ratio 8 dots/mm(384 dots/line ) Life of print head 50km Printing speed 20mm/second (when power supply is 5V) Character size 9x17 dots or 12x24 dots Chinese character library GB2312, 16x16 dots, 24x24 dots Paper supplied Thermal roll paper (57mm wide, ￠30mm) Interface USB/serial RS232/TTL/485/parallel interface Input power 5V DC, 3A Operating temperature 0 to 50°C Storage temperature -20 to 60°C Operating humidity 20 to 85% Storage humidity 5 to 95%