[This review was collected as part of a promotion.] I purchased this mouse with a new ThinkBook laptop. I intended to use it for work and online trading. Mouse moves too quickly, doesn't click when I need it to and I can't seem to adjust it. Worse, no user guide came with it so I had to rely on Google searches for information. I realize it's only a mouse but what are the two buttons on the left side? Oh, it's volume up and down. Who knew and did I need that in a mouse? No explanation provided. Also, I don't think this is a very ergonomic device. It's high and doesn't fit my hand well enough to use the middle finger for scrolling. Result is my wrist feels sore. Not good.