The Fishfinder Blue Series is designed for offshore fishing enthusiasts. The Fishfinder 100 Blue operates at dual frequencies. With the 50/200 kHz transducer, you can reach greater depths and get a wider viewing area. And you will see those returns on a crisp, four-level grayscale screen for excellent separation and contrast. This seaworthy fishfinder is rugged and waterproof. But despite its tough exterior, it's extremely easy to operate, with features like a convenient adjustment bar that gives you access to the most commonly used fishing settings. The Fishfinder 100 Blue boasts increased power and dual frequency of 50/200 kHz, which makes it ideal for the saltwater environment. Improved screen contrast and increased image update rate also set it apart from its freshwater counterpart. From the outside, the Fishfinder 100 Blue will resemble its freshwater version, with the size of the waterproof case and the keypad configuration remaining the same. The real changes can be found on the inside with increased p