Beckett Rocket Wireless Fuel Level Monitor The Beckett Rocket is a wireless ultrasonic fuel level monitor complete kit which includes Receiver, Transmitter, 2 NPT adapter, 2 mounting screws, and instructions The receiver displays the oil level as "bars", where each bar represents 10% of the tank's capacity. Provides visual and audible warning when oil is low Can be installed on vertical tanks, horizontal tanks, or any tank up to 10 feet tall! Installs on inside or outside tank in under 10 minutes