…I can use either hand to do my mouse selections. I have a problem with my right arm and hand and could barely use them. The RollerMouse gave me the option to use my left hand and still complete my job duties. I have since been diagnosed with Parkinson’s disease and now with the proper medication my right side is much better. However, since I had the opportunity to train my left hand to do mousing functions, I can switch over to my left hand when the right side becomes fatigued.