Dura-Link Cable Plug for All 4C OFFROAD Jacks is an OFFROAD Plug for Nexus style jacks. Ideal for use when disconnecting helmet kits, it acts as a protective seal against water, dirt, and debris, especially during vehicle cleaning or outdoor activities. However, STX cables and jack mounts are not compatible with Dura-Link Cable Plug, and a version without duralink is available as #OFF-PLUG-NW.