The Cam-10 is the circuit alert unit that detects electricity for all of our Circuit Alert tools. This sensor takes two LR44 button style batteries. For a detailed instructional video on the battery installation for the Circuit Alert (CAM-10) unit attached to your tool, please follow this: LINK!
To install the batteries in this tester, you will need to remove the battery cover, which is located at the rear of the unit. The cover is the strain relief that connects the wire test lead to the body of the unit. You will need to twist the cover to remove it.