Features Specifications:Sell LED Name Card  LED display card operation instructions:  1) Presses "K1" to turn on the LED display card, it will displays "AAA" 2) Presses "K2" to choose the group (there are 6 groups altogether, among   which the 1st group can store 512 characters, 5 other groups can store   256 characters), after you choose the group, confirm according to "K1" 3) Presses "K4" to choose the character form you want to display (There are   capital letter, small letter and special character for you to choose, please   see the blank as below) 4) After choosing the character form, you can press the "K2" or "K3" to choose   the letter or the special character you want to display. Confirms according to   "K1" after selecting a letter or the symbol each time. After you press the   "K1", you find that the letter you choose is wrong, then you can press "K5"   to correct it. That is, first press "K5", then press "K4" to choose the   character form you want to display. After that press the "K2" or "K3" to   choose the letter or the special character you want to display. Confirms   according to "K1" after selecting a letter or the symbol. After the correction   you can continue to input what you want 5) Waiting for 10 seconds, it will show automatically after all choosing the   display information wanted 6) The speed shown amounts to 9 grades, you can change its speed under   the state that it is showing according to "K4". One of the grade can make   the displaying stop don't move 7) You can press "K1" to take off it under the state of displaying 8) Operated by 2pcs CR2032 batteries