With the LINDY RJ-45 Port Blocker, you can quickly block open network ports and easily prevent users from connecting cables, devices or inserting foreign objects without permission. This helps protect against unauthorized access to a network or system, as well as preventing unintentional or malicious damage to ports. It can also act as a visual cue, showing inactive or disconnected ports. To use, simply attach a blocker to the key and plug it into the port. Hold the blocker in place and pull away the Key. To remove, simply insert the Key back into the blocker until it 'clicks' and pull it away. Easy!