Important note of single controller and single LCD display choice. A. LCD display looks the same in appearance with 3 key, While there is 2 connetors, 5 + 1 pin, 4 + 3pin. The one we have is 1 connector with 6pin. It doesn't work if you choose single lcd or singel controller. B. The LCD is totally the same in appearance and with 6 pin connector. Within the protocol it differs from different vendors. Single LCD or controller won't work if the protoicol is not match Application Foldable scooter spare controller, Wheel 4 inch 5 inch 5.5 inch 6.5 inch 8 inch 8.5 inch, power 350w and below Carbon fiber scooter controller kit Controller Installation size regulator 86 x 46 x 38mm Technical data P0, the lack of volatge (battery voltage below this does not work) P1, wheel diameter, (5.5) P2, motor pole pairs, (usually for 5.5 inch is 20) P3, is the choice of speed signal (speed from hall sensor or LCD meter) P4, it is km or miles. 0 is km, 1 is Miles P5. 0 is zero starting, 1 is not. P6 Cruise choice. (it is related to the scooter model). 1 is yes. 0 is no. P7. Soft start choice (is linked to the scooter model) 0 is soft start. 1 is difficult P8, ODO to zero. Clear record mileage Colour: black Material: plastic Package Contents: 1 * Controller 1 * LCD Monitor 1 * Brake Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.