Yes, Paul - it is just that. I usually incorporate them into the tip portion of the control surface, but have made many others from streamlined coffee sticks with streamlined lead weights epoxied on. The stick faces ahead of the hinge line at an angle that is just sufficient for the arm to clear the wing or stab at full deflection. This type is easy to rig up for a quick test; later you can do a more sanitary job. It is important not to overdo the weight - too little is much better than too much, since excess balancer weight can excite higher harmonics that can be very destructive.