This product is either discontinued or we cannot get that from suppliers.
Garmin Transom Mount 010-10249-40, Black, Frequency (kHz): 77/200, Power (W): 500, Beam Width (Deg.) LF/HF (-3dB): 45/15, Max. Depth (ft.): 1900, Depth/Speed/Temp: D/T, # of Pins: 8, Cable Length (ft.): 30, Supported Deadrise/Transom Angles: 0-70 Deg. Transom.
Garmin 010-10249-40 Dual Beam. This dual beam transducer replaces the one included with your echo series fishfinder.