This was purchased a while ago to connect a Celestron Nexstar eq6 PC hand controller to a PC. It is not a genuine product, and its operation has not been confirmed, so please understand. Cancellation is possible if it doesn't work. (Please return it by standard mail) USB to RJ11 RJ12 Control Cable for Celestron Nexstar eq6 PC Hand Controller RS232 Serial Conversion Cable For reference: https://www.amazon.co.jp/%E3%83%8F%E3%83%B3%E3%83%89%E3%82%B3%E3%83%B3%E3%83%88%E3%83%AD%E3%83%BC%E3%83%ABPC%E6%8E%A5%E7%B6%9A%E3%82%B1%E3%83%BC%E3%83%96%E3%83%AB-Celestron-Nexstar-FTDI-RS232%E3%82%B7%E3%83%AA%E3%82%A2%E3%83%AB%E3%82%B3%E3%83%B3%E3%83%90%E3%83%BC%E3%82%BF%E3%83%BC%E3%82%B1%E3%83%BC%E3%83%96%E3%83%AB/dp/B082GVR8DF Celestron Nexstar eq6 Hand Control PC Connection Cable FT231XS USB to RJ11 6p4c Hand Controller RS232 Serial Converter Cable for PC connection. Option 1: For Celestron NextStar. This option provides basic mount control from a PC using the Celestron NexStar driver. If you have a mount for the SynScan hand controller, you can use this function as is. This cable is used with your PC and connects to the hand control box for the Celestron Nexstar eq6 telescope. Before SynScan V3.01, the hand controller needed to be placed in a special "serial mode". From SynScan V3.01 onwards, the hand controller is always in serial mode and can always communicate via a serial connection.