Garmin STRIKER 4 CHIRP Dual-beam Transducer Fish Finder with GPS -  Easy-to-use 3.5-inch color Fish Finder with built-in, high-sensitivity GPS. Find fish; mark and return to hot spots, docks and ramps. Convenient keypad operation. Includes CHIRP (77/200 kHz) sonar transducer; transmit power (200 W RMS)/(1,600 W peak-to-peak) Upgrade to high performance CHIRP with a GT8 or GT15 transducer (each sold separately) Finding fish is easier than ever with STRIKER 4 Fish Finder. Mark and return to your hot spots, boat ramps and docks, and share your favorite waypoints and routes with other STRIKER and echoMAP combos. Smooth Scaling graphics provide uninterrupted imagery when switching between depth-range scales. Sonar history rewind allows you to scroll back through sonar images to mark waypoints you originally may have missed. Plus, it has a built-in flasher and displays speed data. Includes CHIRP (77/200 kHz) transducer with mount. For high-performance CHIRP, purchase a GT8 or GT15 transducer (each sold separately). Experience the Clarity of CHIRP STRIKER 4 Fish Finder includes a Garmin CHIRP (77/200 kHz) transducer, which provides a visibly higher level of clarity and detail for fish and structure than traditional 77/200 kHz transducers. Instead of sending just 1 single frequency, CHIRP sends a continuous sweep of frequencies, ranging from low to high, then interprets them individually upon their return. Since the frequencies provide a wider range of information, CHIRP sonar technology can create crisper fish arches with greater target separation. You also can upgrade to high-performance Garmin CHIRP technology, which provides crystal-clear sonar images with even more remarkable target separation and resolution from shallow to deeper depths. For better fishing, bottom contours are more visible, even at higher speeds, and signal noise can be suppressed at greater depths to provide a timelier interpretation of what’s below.   Mark Spots with High-sensitivity GPS Unlike regular Fish Finders, STRIKER Fish Finders have built-in, high-sensitivity GPS to locate your current position quickly and precisely, then maintain your GPS location anywhere you go on the lake. More importantly, they allow you to mark spots where the fish are biting so you can return to them again in the future. You also can mark docks, boat ramps and other locations on the lake. Just follow the path created on your screen to return to them whenever you wish.   Navigate Easily with Waypoint Map Since the STRIKER Fish Finder series includes high-sensitivity GPS, you can see your position in relation to waypoints you have marked. Use the waypoint map to easily view, mark and navigate to locations such as brush piles, stumps and docks. It’s also a great tool for finding your way back to the boat ramp.   Check Your Speed on Screen You can quickly and easily see your boat’s speed on the screen of your STRIKER Fish Finder. It’s a great tool to make sure you are trolling at the right speed for the lure you’re using and for a particular fish species. It’s also a good way to tell if you are going the right speed in wake-controlled areas.   Fish Vertically with Built-in Flasher STRIKER provides you with both a Fish Finder and flasher all in 1 unit. Anytime you are stationary fishing, such as ice fishing or jigging for crappie, the built-in flasher will show you the bottom, whether it is solid or muddy, your jig or weighted bait, and the depth of fish as they swim into the sonar beam. You can even watch how high your jig is being lifted and dropped and whether fish move toward or away from it.