Note :If you choose the cheapest one , it is only water level gauge Without sensor Water Level Gauge Specification:- Material: PC Polycarbonate - Size: Approx. 8x8x7cm/3.15x3.15x2.76inch - Working voltage: 9-32V - Working current 60mm - Working temperature: -30~+75C - Gauge diameter: 52mm / 2inch -Warning Light : When Water level less than 13%, the warning light will flash . - Signal :0-190ohm/240-33ohmLiquid Level Sensor Specification:- Protection ank: IP67 - Resolution range: 21 mm - Assembly: SAE standard 5 holes - Rated current for alarm switch: 500mA - Operating temperatures: - 40 to 85 Celsius - Fit for Fuel Level Gauge and Water Level Gauge - Sensor Length :150mm/200mm/250mm/300 mm ,350 mm and so on - Mounting: 5 pieces of M5 screws and 2 mm thick gasket - Output signal: 240-33 ohm (Standard American),Package 1 Include:1 X Water Level Sensor 1 X 52mm Water Level GaugePackage 2 Include:1 X 52mm Water Level Gauge