The Garmin GNS 430 is the most versatile panel-mounted product GARMIN has produced to date. It combines GPS navigation, VHF communication, and moving map graphics on a big color display.

Garmin GNS 430 GPS Nav/Com
This "all in one box" 12-channel unit offers IFR GPS, ILS, VOR, LOC and glideslope capability in a single, space-saving package.  Having dual Garmin 430's allows an added measure of safety and convenience, allowing true multi-tasking in a variety of crucial navigation functions.  Briefing approaches, looking up information, calculating winds aloft, altering flight plans, and a host of other functions can be accomplished on the backup unit, while leaving primary information intact on the primary unit (which is usually the unit driving the Sandel HSI and the autopilot.