The HDS units are FANTASTICThumbs Up locators/GPS. They have features that are endless. The DownScan overlay feature helps you understand:Hands Clapping how the structure sets in the 'sonar' cone. I teach new owners to focus on just 3 pagesbanghead whlie learning. Maps, sonar & structure. These should be easier to get familar with & will get you fishing right away. As you get used to these pages,,, get out the owners manual,,, and learn to do a screen shot. If ya need any help,,, contact me or Shane & we'll hep ya <*)}}}><