Engine Block Heater ,self-circulation Engine Water Heater Black Preheater For Generators Trucks Gas Engines 240v - 1000w 1. Made of metal, it is extremely easy to maintain and replace spare parts;2. Equipped with high-end precision processing heating tube, the heating time is short3. Insulation resistance: equal 10Mohm4. Electric strength: 1500V/1min (normal)5. Temperature control range: 40C-50CThe working principle of the heater: low-level cold water enters, hot water from above, a heating pipe, a temperature controlColour:blackMaterial:Metaltype:1000WPackage Contents:1x Engine Block HeaterOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.