SDD-110 Seawater Depth Indicator - Display OnlyThe SDD-110 operates on working frequency of 120kHz, so it won't interfere with other onboard echosounders. This compact unit - measuring only 4.3" X 4.3" X 3.5" - uses Digital Signal Processing (DSP) technology to deliver accurate digital depth readings from 1.5' to 1,375' in easy-to-read numerals. The large four-digit LCD display offers five levels of backlighting, for optimum visibility in all ambient light conditions.Because the SDD-110 is a one-piece system, it doesn't require a black-box sounder or the complicated wiring associated with network sounders. Instead, the 120kHz transducer plugs directly into the back of the unit for fast and easy installation. The SDD-110 uses an inexpensive flush-mount 2" thru-hull transducer with a 38-degree beam angle. This allows for easy installation and proper beam orientation on most hulls without the need for a fairing block.In addition to providing precise water depth data, the SDD-110 also features a visible trend indicator to indicate if depth is increasing or decreasing. Audible alarms also alert the operator to dangerous shallowing conditions or if the water drops below a selected depth - useful for fishing.The SDD-110 also features NMEA-0183 depth data output that can be interfaced with other onboard equipment. Similar to SI-TEX's popular SST-110 temp gauge, the SDD-110 is a drop-in replacement for the venerable Datamarine Offshore Digital Sounder, popular for many years on numerous sportfishing vessels and workboats.