‎DT1H Handheld Depth Finder with Temperature, 300 Feet. The most versatile handheld depth finder sonar system ever produced. Water depth readings from 1.5 to 300 feet (.5 to approx. 90 M); Automatic depth range adjustment. Water or air temperature readings which are displayed in degrees farhrenheit or celcius on a SoftGlow backlit LCD display. Inductive switching technology (IST) allows the unit to be 100% waterproof up to 200 feet (approx. 61 M). HawkEye products are manufactured both in the USA and overseas using technology designed and developed with American ingenuity.