Ergonomic mouse, new definition of grip censi mouse is based on the most advanced hand shoe mouse ergonomic design,providing an ultimate solution to prevent rsi and carpal tunnel syndrome. by extensive experiments and data analysis, p.h.d erik pepper from usf defined a perfect angle of 33 degree that hand and fingers are fully supported at the ideal angle of 33 degrees makes sure fore arm completely relaxed and naturally stretched out of the tension state of the arm bone to control the mouse by the logic as below: reduces wrist and forearm pronation the concave depression on the thumb rest of the mouse combined with the downward slope at a 33°degree; angle off the horizontal, which is a more natural position for your wrist and forearm. reduces wrist strain due to excessive movements with the ergo-grip detachable flange, control the mouse with your whole arm instead of wrist or fingers that only need a minor effort to switch while your thumb rests on .