Product selling points: 1. Digital display of temperature and voltage, intuitive observation, accurate and stable parameter display. This circular panel voltmeter is convenient for reading, and monitors the battery voltage in real time, so that you can know the power status in time. 2. Made of high-quality pc material, it is flame-retardant, impact-resistant, simple to install, stable in performance, high-quality material, durable. 3. Low power consumption, used to monitor battery voltage. With reverse connection protection function, the circuit will not burn out, waterproof and durable, safe and reliable to use. 4. Small size and easy to store. This product is 36cm long, 24cm wide and 27cm high. It is widely used in electrical products that require power. 5. It is suitable for the installation and use of all 12V voltage vehicles, such as automobiles, motorcycles, buses, ships, RVs, yachts, trailers, etc. Specifications: Material: PC Input voltage: 12V Operating temperature: -40 to 80 Shell color: black Aperture color: red, blue Size: 3.7cmx3.6cmx2.7cm/1.46inx1.42inx1.06in Weight: about 15g Note that this model does not have a cable: red and black positive and negative power cables can be equipped with fuse overload protection, the cable length is 60CM or 150CM, or the length is customized. Need to buy separately Product list: temperature voltmeter + 2 * blue terminal + fixed ring