We use our mouse a lot throughout the day. It is therefore essential to use a high-quality ergonomic model. This wireless Evoluent 4 is a vertical mouse. You hold the mouse in a <(>&<)>034;handshake<(>&<)>034; position. Your wrist and lower arm will not have to bend and rotate as much. When using the wrong mouse, you may experience... pain or discomfort in your shoulders<(>,<)> lower arms or hands. A vertical mouse can prevent these issues. This model has a short acclimatisation period. .ent 4 enables working in a comfortable natural position.