: Located on one outer edge. This provides the primary 20V DC output to the tool.
Imagine looking at the battery’s connector slot. The terminals run along the top edge: Hart 20v Battery Pinout Diagram
Helps the tool or charger recognize the specific battery pack, which can prevent "unknown" or incompatible packs from being charged. C (Control): : Located on one outer edge
. These measure the voltage of individual cells in the series: Common Troubleshooting and Usage Low Voltage Protection: Hart 20v Battery Pinout Diagram