Compatible with: GSI GSI39, GSI TympStar, GSI TympStar Pro, GSI GSI18, GSI GSI 61, GSI AudioStar Pro, Interacoustics AS608, Interacoustics AD226 New, Interacoustics AD629, Interacoustics AC40, Interacoustics AD528, Interacoustics Affinity 2.0, Interacoustics Equinox 2.0, Interacoustics Callisto, Interacoustics Affinity Compact, Natus-Otometrics Aurical, MAICO MB11 Classic, MAICO MB11 Beraphone, 2m/6.56 feet.