The Global Parts Distributors Temperature Tester, No. 5811585 allows technicians to easily and quickly measure the temperature performance of an automotive air conditioning or heating system. It can also be used to detect restricted condensers and heater cores. The screen displays inlet and outlet temperatures and the differences between them. The Temperature Tester probes are color-coded blue and red and the clamps are designed for easy attachment, even in difficult-to-reach areas. Easy-to-follow instructions are included as a reference guide.