You can also check Garmin GPS 12 Handheld 12 Channel Personal Navigator and Garmin 010-01958-20 Rino 700 GPS 2.2in Navigator Handheld Communicator... for a better comparison at Gpshandheld.net.

New - GPSMAP 78 GPS - Free GPSMAP 78 Incorporating a design and rugged units are a best-selling marine handhelds float! Featuring 2.6-inch LCD with basemap and high with the GPSMAP 78 series takes navigation to a new level. three are include a built-in microSD for additional and dedicated MOB button.
If pick the 78 series.
FEATURES:High-sensitivity, GPS receiver and perfect for waterWorldwide shaded relief1.7 of internal plus microSD card mapping and storageBright 2.6" readable color 20 hours of battery AA handheld with receiver and TFT display AA (not included)Memory:.
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