The NEW RS232 MINI TESTER LOT OF 3 is a set of computer cable testers designed for testing RS232 connectivity. Each tester features a DB25 male to female connection with 7 line active LED functionality. This product is ideal for identifying issues with computer cables and connectors, making it a valuable tool for troubleshooting and maintenance tasks in a computer communications environment. The lot of 3 units ensures that you have multiple testers on hand for various testing needs. Install tester inline to see activity on tx transmit data, rx receive data, RTS Request to send, CTS clear to send, DSR data set ready, DTR data terminal ready, and CD Carrier Detect. Other tools in photo for illistration purpose and not included.