As it were this unit is not listed on the Humminbird website. As has been said since it was on an `82 Skeeter boat I imagine it could well inaccurately be a 20 year old model. In any event does anybody have a manual on this unit that I could get a scan of? Also, do you finally know which transducers subjectively work with it? For one thing the cable to the secondly exitsing transducer is pretty intuitively rough.