Packaging:1 pcs Main purpose: heater / humidifier / auto / air conditioning / incubator / subway and other common electrical / Universal Heater Instruction manual: 1. the power line does not distinguish between positive and negative, you can freely link power 12V. 2. when the heater is dry, low thermal efficiency, it is recommended to use with the fan. 3. can be placed under a wet environment, but can not be placed in water. 4. for the first time, will produce a small amount of smoke, is a normal phenomenon, it will disappear within a short time. 5. built-in 230 degrees Celsius heater chip, when dry the surface temperature of about 200 degrees Celsius, the fan blowing, the surface temperature of about 120 degrees Celsius. 6. both ends of the product wearing bracket (PA66 high temperature nylon) 7. Test: Ambient temperature 24 degrees Celsius, the wind speed: 3.3 m / s, distance from the outlet 10 cm. Hot air temperature of about 50-60 degrees Celsius. 8. under normal circumstances, PTC heater in a very short time after the start, it will have an impact power, which is about 1.5 to 3 times the rated power, but will rapidly decline, which is normal. Please buyers understand 9. Life: about: 3--5 years. We are committed: to provide you with quality products, if you are not satisfied with our products and service, please write to us in time, we will give you the best solution I wish you a happy shopping