Dbstar asynchronous LED card is primarily designed for LED display sign in small size/low resolution such as 640×480 or 800×600. It allows users to operate the LED screen without computer connected. This kind of controller card is geared with a storage slot of 4~8GB SD card. You can just simply plug in the SD card with the ready programs to be played. WiFi control mode is also available. The popular asynchronous controller cards sold in the world market are 09 version asynchronous controller system (DBS-ASY09C),09 version asynchronous controller system (DBS-ASY09NC), DBS--ASY11C LED display card, DBS-ASY13C asynchronous control system, etc.