The Furuno LS4100 is a 5-inch, waterproof marine GPS receiving system with a keypad user interface. This Furuno GPS receiver is wide-area augmentation system (WAAS)-enabled, which helps to ensure accurate placement of the vessel point on charted system maps. The four-level, grayscale LCD display screen allows the unit to be viewed easily in any weather conditions. The 240x320 screen resolution of the Furuno LS4100 helps provide clear images. Technical marine features for this GPS receiver include a fish-finder and a sonar/sounder feature to ensure that there is never a dull day of fishing. Audible features of the Furuno LS4100 include the arrival alarm, fish alarm, low battery/voltage alarm, and water temperature alarm. Warm-weather acquisition time for this Furuno GPS receiver is 15 seconds, while cold-weather acquisition time is 55 seconds. Dimensions for this GPS receiver are 6.5 inches high by 7.2 inches wide by 3.7 inches deep. The weight of this unit is 4 lbs.