This is a Nicestuff 68841 (aka NSD-68841) carkit-specific adapter for use with their NSD-series, EZ-series and PR-series carkits integration harnesses. The black connectors on this adapter is designed to plug directly into the Motorola HF850, T605 and T603 (also HFK7200, HFK9250, or HFK9800) carkits. When used with a Nicestuff / KRAM vehicle-specific adapter harness (see the other items in my booth for a selection of harnesses), on activation of the Mute line by the carkit, the vehicle audio will switchover to the handsfree kit. This adapter directs supply of the following connections to the carkit: VBATT - constant +12V power supply Ground - chassis ground Ignition - switched +12V signal Mute - active-low trigger Mute connection Speaker (+) - differential mono audio signal from the carkit or device Speaker (-) - differential mono audio signal from the carkit or device I have a mobile electronics installation business and am selling off some excess inventory. Please feel free to send a message if you have further questions about any of my items. I am willing to ship this item internationally, but please contact me first so that accurate shipping charges can be assessed. Thanks for looking!