Deeper: Smart sonar is a first of its kind, portable, wireless fish finder specially designed for amateur and professional fishermen. High accuracy sonar shots reveal most of the fish species with a crystal clarity, and allows you to target your prey with confidence. Deeper sonar is powerful enough to perfectly function in the depths from 1.5ft (0.5m) to 130ft (40m) below the surface in both salt and fresh waters. Enhance your fishing experience with the detailed view of the bottom terrain, and fish holding habitat using innovative Deeper Smart Imaging technology. Deeper temperature sensors provide accurate fluctuations of the water temperature so you always know the perfect biting time. Size H13.5, W15.5, D7.5cm. Batteries required: 1 x rechargeable (included). Manufacturers 2 year guarantee.