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 unauthorised 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. The semi-permanent RJ-45 Port Blocker is made up of a molded plastic blocking cap that plugs securely into the RJ-45 port with a special insertion key. The blocker latches into the RJ-45 just as a network cable would and remains in place until removed using the insertion key (not included, see part number 40470). 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! Security Note: This Port Blocker will only act as a a basic physical & visual deterrent to tampering. It will not prevent a determined attacker, intent on gaining physical access to a RJ-45 port.