A handheld electronic device includes a reduced QWERTY keyboard and is enabled with disambiguation software. The device includes a concentric and at least four groupings of letters located around the concentric. The handle has a shape and texture to comfortably fit the hand when gripped to perform the cleaning operation requiring short back and forth strokes while bearing down on the tool and grill surface with a moderate amount of force. Means are provided for feeding back the output signal so that the two matched transistors are balanced in response to a change in the input signal appearing at the input terminal. As a hydroxy fatty acid salt, 12-hydroxy lithium stearate is suitably used.