LFD-D31 LED Back Light Name Badges. The Brightness of the screen is like
Cell phone acreen. Can be attached with Key Chian or Necklace Super
Bright white , Blue, Green, RED, Orange, or RGB 7 color LED AD
Paper can be changed anytime (Slide In) CR-1616 Battery * 2 PCS
(6V) 3 Frequencies Flashing IC function Battery:CR1616*2PCS Size:55*23*10mm