Description: 【Efficient Coil Testing】: This solenoid tool is designed for quick and efficient testing of AC coils, making it an essential accessory for HVAC professionals and enthusiasts 【Compact Design】: With a compact size of 5cmx1.6cm, this coil tester is easy to carry and store, ensuring convenience during fieldwork or in your toolbox 【Sturdy Material】: Made from PP, this testing tool offers durability and reliability for long term use in various environments 【Versatile Application】: Ideal for checking refrigeration solenoid valves, this keychain style tester provides versatility across different coil types and applications 【Easy to Use Tool】: Its simple design allows even beginners to quickly assess the functionality of electromagnetic valve coils without any hassle   Size Chart: 5cmx1.6cm/1.97inchx0.63inch Package Includes: 1x Rotation Tester and AC Detector Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement.