Makita cordless tools are engineered for industrial applications, and for added protection during the most demanding jobs Makita created STAR Protection Computer Controls™. STAR is communications technology that monitors conditions during use, allowing the tool and battery to exchange data to protect against overloading, overdischarging and overheating. If STAR detects conditions that threaten to overload, overdischarge or overheat the tool or battery, the tool will automatically stop. At that time the user can either restart the tool, change or charge the battery, and put the tool back to work. When you slide a Makita 18V LXT® battery with the STAR symbol onto a Makita tool that has either the STAR symbol or a yellow terminal, you are benefitting from STAR Protection Computer Controls™.