Abstract: An inline pump assembly for dispensing fluids, the pump assembly including a pump head, having a piston wherein movement of the piston causes the pump head to dispense a fluid. A linear actuator has a lead screw wherein actuation of the linear actuator causes the lead screw to move along a linear path. A first anti-backlash device is disposed between the linear actuator and the pump head. The anti-backlash device includes a rail having a sliding block thereon. The slide block and rail are engaged to prevent movement of the slide block about a longitudinal axis of the rail. A coupler is fixedly secured to the linear slide and having a first end connected to the lead screw and a second end connected to the piston rod.