Greg will jump in here shortly i'm sure, the only thing i've experienced is the Connector Collector is different for the newer/higher number models I believe then the lower number/older models. So depending on which model the transducer was used before it may or may not fit through the Connector Collector. Also, the transducers themselves are not universal, so let Greg know which model of the unit and the transducer you are trying to use, he'll help ya out!