The Car Radiator Fan Thermal Switch 1/8 Inch NPT, with a temperature range from 140 degrees to 125 degrees, is expensive due to its specialized design, high-quality materials, precision manufacturing, and the specific technical requirements it fulfills in automotive cooling systems.

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This type of thermal switch is designed with precision to ensure that it accurately triggers the radiator fan at the appropriate temperature thresholds. This design involves complex engineering and rigorous testing to guarantee reliability and performance under various operating conditions‌.

Moreover, the materials used in its construction are of high quality, capable of withstanding high temperatures and harsh environments without compromising functionality. These materials often come at a higher cost, contributing to the overall price of the switch‌.
The manufacturing process of this thermal switch also requires a high degree of precision. Each component must be meticulously crafted to meet strict specifications, ensuring that the switch operates seamlessly within the automotive cooling system. This level of craftsmanship and attention to detail adds to the production costs‌.
Additionally, the specific technical requirements of this thermal switch, such as its 1/8 inch NPT threading and precise temperature sensing capabilities, make it a specialized component that is not widely produced. As a result, the limited supply and high demand can drive up the price‌
In summary, the combination of specialized design, high-quality materials, precision manufacturing, and specific technical requirements makes the Car Radiator Fan Thermal Switch 1/8 Inch NPT, with a temperature range from 140 degrees to 125 degrees, an expensive component in automotive cooling systems.