Makes it possible to connect your phone holder to an external antenna for improved reception. FME Male connector. Includes TNC Female adapter. Requires phone holder to make connection (sold separately).Compatibility: A2218, A2218z, P800, P900, R300d, R300z, R300LX, T200, T28z, T28 WORLD, T300, T310, T306, T316, T39, T60c, T60d, T60LX, T61c, T61d, T61LX, T61z, T68i, T68m, T610, T616, T637, K700, K750, W800