Described herein is a dispenser for dispensing fluid that, integrated into one hand piece, comprises a variable volume chamber with a plunger disposed within the chamber and a chamber inlet and outlet. The inlet and outlet communicate directly with a common chamber volume and the plunger translates in a linear direction relative to the chamber along a common longitudinal axis to expel fluid from the chamber (expel stroke) and/or draw fluid into the chamber (drawing stroke). The plunger is linked to a controller, a power source and a motor that drives translation movement of the plunger. The dispenser described herein offers a variety of advantages over the art including accurate dosing without the user having the manually regulate the dose amount—the amount to be dosed is related to the volume of fluid in the chamber which can be pre-set or varied automatically using sensors and controllers.
