The Mishimoto water temperature sensor adapter allows you to place the water temperature sensor directly within the radiator hose. By placing the sensor in the hose and thus directly in the path of the water to the radiator, you are ensuring the most accurate reading possible. Being able to accurately gauge the temperature of the water aids in preventing overheating. Each temperature sensor adapter is made of Aluminum. Mishimoto provides free replacement for accidental damages, basically, if you are in an accident and your Mishimoto part is damaged, they will replace it free of charge when you provide pictures and a police report.