44 45 / Using the Mounts ATTACHING THE LOCKING PLUG If you are using the HERO in high-impact sports such as surfing or skiing where significant impact might occur, use the locking plug to securely lock the Quick Release Buckle fingers into place. The locking plug helps to prevent the housing from accidentally releasing from the mount. To Attach the Locking Plug. Loop the circular ring over the thumbscrew. The circular ring acts as a leash to prevent dropping or losing the locking plug. Slide the Quick Release Buckle into the mount until it clicks into place. Press the U-shaped part of the plug into the U-shaped space in the Quick Release Buckle.