This is the Depthmate Portable Sounder Floating Electronic Depth Meter Features: Use it before, during or after your dive Will read through a solid hull, inflatable bottom or black ice Extremely accurate to the nearest 10th decimal Backlighting Display for Night Diving Available with External Transducer - can be used from larger boats, mounted inside or outside of the hull, on a pole or boat hook This is useful if you are not close enough to the water to use the SM-5 (see below to order) RANGE: 2-260 feet DEPTH: 160 Feet WEIGHT: 10 oz (with battery) User changeable Imperial/Metric COLOR: Yellow Anchoring security for cruising sailors! Find deep water easily from your dinghy. This unique pocket-sized depth sounder is very accurate and of very high quality. It is useful for boating, fishing, scuba diving, coastal survey, and scientific work.