The SAE Short Circuit Connector Tester detects the presence of voltages and signals in SAE harnesses. ATTENTION!!!When the tester's LEDs are illuminated, the cable is properly energised.No light means wrong polarity. SAE Polarity Reverse Adapter,If the polarity of the SAE port to be tested does not match the polarity of this tester, you will need to use a polarity reversal connector to convert the polarity before you can test accurately. SAE Short Circuit Connector the male port is "+" , the female port is "-", and the voltage of the SAE power line under test should be within the range of 3-36V. Plug and play, strong and durable. Small and lightweight, easy to carry.Easily Detect Solar Panel Plug Power Cord Connections. Colour:Black Material:Metal+Plastic Package Contents: 2x SAE Short Circuit Connector 1x SAE Polarity Reverse Adapter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.