Feature: 1. Application: The sender is designed with non linear output, it can only match standard gauges with non linear signals. Suitable for boats, yachts, trucks, RVs. 2. Unique Design: The doughnut float design type level sender is durable and reliable in use, and no moving parts to break, no adjustment needed for tank. 3. Material: All fuel sending units are made of reed switches and fixed resistors. SAE 5 hole mounting pattern, heavy duty 316 stainless steel and sturdy construction. 4. Complete Accessory: Fuel level sender is equipped with gasket, mounting screw, in order to keep the sender from touching the bottom of the tank. 5. Applicable Hole Size: The float is 1.38in (35mm) in diameter. If you must drill holes, a 1‑1/2in (38mm) diameter hole would be perfect. Specification: Item Type: Fuel Sending UnitMain Unit: 316 stainless steel Cable: PVC Float: NBR Installation: Standard SAE 5 hole type Screw Size: M5 x 0.8 Aperture: Approx. 5 mm / 0.20 in Product Size: Approx.12in/300mmRecommended Water Tank Size:12.3in-13in(310-330mm) Resolution Range: Approx. 21mm/0.83in Fuel and Water Level Sensor Type:Resistance Alarm Switch Rated Current: 500mA Protection Class: IP67 Operating Temperature: -40°F ~ +185°F (-40°C ~ +85°C)Application:Suitable for boats, yachts, trucks, RVs. Package List: 1 x Fuel Sending Unit5 x Screw1 x Gasket Note: 1. This fuel tank sensor is 240‑33 ohm, only suitable for 240‑33 ohm fuel gauge. Please make sure your product is suitable for 240‑33 ohms before purchasing. 2. When the oil level or water level is empty, there will be 3‑15mm space between the sensor float and the bottom of the sensor. This is a safe distance and the fuel sender will work fine.3. Please check the size and description of the product carefully before purchasing, if the fuel tank is plastic, the length of the gas tank liquid level sensor should be 1in smaller than the depth of the fuel tank, if the water tank is metal, the length of the liquid level sensor should be smaller than the depth of the fuel tank 0.5‑1in