I find my Garmin 315 a handy piece of kit that fits in my pocket. The blurb is; 6.0 X 2.0 X 1.3 inches (158 X 50 X 33 millimeters) and a high resolution (104 X 160), 4 grey shades display. When fitted with 2 AA batteries, weighs 7 oz. (199 gram) and has about 10 hours continuous life between changes. It has all significant UK towns in its map memory and the cold startup time is about a minute. A fuller picture is on
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