Water depth meter with digital display.You can measure the length of the line when rewinding, as well as on the shelves.Installation is completed simply by sandwiching it with the rod clip.When tension is applied and the line is released, the digital counter will count every 0.1m (=10cm)/0.3ft.The count unit can be switched between m (meter) and ft. (feet) with one button.Equipped with a memory mode that allows you to register up to 10 water depths. Diameter for rod: 12 ~ 23 mm;Minimum measurement unit (m/ft)-0.1/0.3;Battery used:CR2032 x 1 (sold separately)