At a minimum I need the power cord and unit head. The one in my dash works and already has the shoot-thru hull transducer that will work with these units (192 hertz). The X51 and above uses the newer 200 hertz xducers, however anything bigger than the X51 or X52 will not fit between my dash guages... I tried Ebay and yes they have them but there are some folks in this world with more dollars than sense (Outbidding someone is not a sport to me but seems to be for some).... I'll buy a new X52 and epoxy in the new xducer before I pay a ridiculous price, especially on Ebay...... reply or shoot me an email ...... tight lines