◆Big color OLED screen, anti-seismic and knock ◆Rechargeable design, avoiding the trouble of changing batteries frequently, long stand-by time ◆Can register 399 numbers at most ◆10 numbers scrolling display ◆Prompt: beep, vibration, beep& vibration ◆Screen Size:1.6*2.1*0.6 in (40*52*15mm) ◆Assorted with charged software, users can define the showing information, advertisement information and colors. Can also make registration more simple. ◆Use a charger