fishwater is partially correct, it will work for ALL models prior to Helix G2’s. An additional note, this will work for Helix G2 models also, just won’t have the ability to utilize CHIRP, just the traditional 83/200kHz frequencies.
This IS the transducer for Humminbird display depthfinders.
This is NOT the transducer for Humminbird 35 or 55 flasher units. Those flasher units take the XI 9 19 ice transducer.