Garmin GPS etrex10

Rugged hand held navigator with preloaded around the world basemap and 2.2-inch monochrome display
WAAS-enabled GPS receiver with HotFix and GLONASS Toughen for speedy positioning and a reliable signal
Water-resistant to IPX7 standards for protection against splashes, rain, and so forth.
Toughen for paperless geocaching and Garmin spine-mounting accessories. Power with two AA batteries for as much as 20 hours of use (perfect with Polaroid AA batteries)
See low and high elevation points or store waypoints along a track (get started, finish and high/low altitude) to estimate time and distance between points