George the unit your talking about comes w/the correct Transducer for it so don't worry about it just use what comes with it! problem solved!!!!georgemro said:Looking to buy a Lowrance a HDS-7 Gen2 with stucture scan to mount at the bow/trolling motor but don't know which transducer I need. The transducer in the catalog looks the same as the old trolling motor transducers. Help please.