This mouse also has pairs of left and right button. For the second pair, you must use your thumb and fourth finger to control. By using other fingers, you can have your index finger and middle finger rest for a while.
The slope angle of this mouse is adjustable. You can change the positions of your wrist while using the mouse, so that your wrist will not get tried that easy.
This mouse has a very big wheel so that you can roll the wrist on table as well as by your finger. Sometimes when we are browsing a long document, our fingers may get tried of rolling the wheel. This mouse can help you rest your fingers.