Disclosed is an applicator comprising or including, a dosing body including, at least one barrel; a piston moveable within the at least one barrel to stroke between a variable first position and a second position. In use, movement of the piston towards the first position can draw a first fluid into the barrel, and movement of the piston towards the second position can force the first fluid out of the barrel. There is at least one fluid inlet valve to allow the fluid to flow into the at least one barrel at least under action of the piston, and at least one fluid outlet valve to allow the first fluid to flow out of the at least one barrel at least under action of the piston. A piston actuating assembly, selectively engageable with the dosing body, is present, the piston actuator assembly having a user operable handle to drive a second actuation member which in turn can drive the piston between the first position and the second position, the connection between the second actuation member, or part thereof being a releasable one.