Try this #1800 633 1468 for questions they are always more than willing to help. These options probably are not considered in high demand right now for pratical fisherman. Although they would be nice to have. They have limited space for things in an already large and exspensive unit. Humminbird asked the military for help designing these units and they said they already had alot invest in their way more exspensive systems, but most search and rescue boats have a side imager onboard now. We are lucky to have the compact 797 version already.