The GPSMAP 188 has a built-in 12-channel WAAS receiver, which means that it can pinpoint your location and other map features within 3 meters on average. The built-in worldwide basemap provides coastline detail, US tide data and inland cartography. The detail gets even better when you plug in an optional data card containing Garmin's exclusive BlueChart marine cartography. The MAP188 offers quick map redraws using a high speed RISC processor. The waterproof housing contains a high resolution FSTN screen with 240 X 360 pixels on a 5.5'' screen. 10-levels of gray including backlighting for sharpness in any light. 500 waypoint and 50 route memory provides plenty of room to store all your favorite locations. Position formats include Lat/Long, UTM, Loran TD's, Maidenhead, MGRS and user grid. Audible alarms for anchor drag, arrival, off-course, proximity waypoint and clock. Trip computer provides odometer, stopped time, moving average, overall average, total time and max speed. The GPSMAP 188 is available with a internal quad helix antenna or an external antenna with 30' of cable. Also features built-in celestial tables for best time to hunt & fish; sun & moon calculations; and tide data for the entire US. Add a 500 watt (RMS) dual frequency (50/200khz) fishfinder and you have an awesome electronics package in one compact unit. The GPSMAP 188 Sounder has auto bottom tracking with 2x and 4x zoom levels. Split screen options to view both the ChartPlotter and sounder at once. Graphic whiteline for clear image of bottom hardness and structure. Underwater waypoints allow you to capture position and depth at your favorite fishing spot. See-Thru technology separates fish returns from thermoclines and structure. The fishfinder operates on a 40 degree beam in 50khz and a 10 degree beam in 200khz. 1000' depth range. Includes; unit, antenna, powercord and owners manual. Dimensions: 6.18''H x 6.3''W x 2.6''D.

Garmin BlueChartTM Offshore Marine Cartography
Complementing Garmin's new line of handheld mapping units and marine chartplotters, BlueChart cartography is designed to provide interactive viewing of detailed nautical chart data. BlueChart provides navigators with innovative object oriented cartography. Descriptive details for features typically found on nautical charts can easily be viewed with a simple key press. Cursor movements over the chart provide descriptions for contour depth, chart number, navaid name, and much, much more. When displayed on a Garmin chartplotter, BlueChart offers you a paper chart-like appearance. This data will include shaded depth contours, inter-tidal zones, spot soundings, wrecks, navaids, port plans, restricted areas, cable areas, anchorages and more. Additionally, BlueChart includes chart numbers, name, scales, revision dates and Notice to Mariner dates. BlueChart offers detailed paper chart-like, vector cartography in large coverage areas so choosing your desired region is easy.