A power tool system includes a base unit having a rechargeable lithium-ion battery, a battery charging system, a power control system and a power output connection. A plurality of head units is configured for use with the base unit. Each of the head units includes an electrical input connection. The electrical input connection is configured to be electrically connected to the power output connection when the head unit is attached to the base unit. Each of the head units is configured to use the electrical power provided by the base unit to perform a different tool function.