Add a physical retention measure to installed equipment with a master-keyed tether. The tether secures a device to an appropriate fixed point, helping limit unauthorized removal while preserving keyed access for authorized personnel. A master-keyed arrangement is suited to environments where equipment access must be controlled rather than left unsecured. SNT-NBLK-SL-10 is a Yealink master-keyed security tether for deployments that need a dedicated physical-security accessory. Use it where a device must remain at its assigned location, such as shared work areas, reception points, meeting spaces, or other accessible installations. The tether addresses physical retention; it does not replace device authentication, access controls, or network security. The distinguishing characteristic is its master-keyed locking arrangement. This enables an access hierarchy around the tether rather than relying only on an unsecured attachment point. Select this accessory when the required outcome is controlled physical attachment with keyed release. Verify the device-side attachment method and the intended fixed anchor point against the equipment and installation environment before deployment.