Model Number: WH-E31 thermal printer Serial 232C 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 6x10 character lines Printing speed 60mm/sec(when the utilization rate is 25％) character size 6x8/8x16 or 12x24 dots Chinese character library GB2312, 16X16, 24x24 dots Paper supplied Thermal roll paper (57mm wide, 30mm) Interface Serial RS232/TTL/485/parallel interface Input power 5-8.5V DC, 15W/9-24V DC, 30W Operating temperature 5 to 50°C Storage temperature -20 to 60°C Operating humidity 10 to 80% Storage humidity 10 to 90%