The sensation of hitting with the Protector can best be described as damp. Head deadens the feel by building on its piezoelectric-based Intelligence technology, used in Liquidmetal racquets, which can convert vibration into electrical energy and vice versa. When the Protector hits the ball, the piezoelectric fibers in the throat produce an electrical output that’s transmitted to a microchip embedded in the handle. The chip instantly analyzes the electrical impulse and sends back a countervailing vibration to cancel out the shock. Of course, if you want to “feel” the ball and know when you hit the sweet spot, this isn’t for you. But players with arm problems should love the Protector, which is available in two models. The oversize is powerful, with a head-heavy balance that makes it a bit cumbersome. It’s best for low-level intermediates with compact strokes. The mid-plus delivers an outstanding blend of power and control for players with medium to somewhat longer and slower swings.