just a bit with the weight of one battery but you don't feel it while using it. I tried some bluetooth mouses before this one that used 2 batteries and I had wrist pain and returned them. this one is great no pain.

@@CNCTinker thanks for the reply

@@CNCTinker i just ordered a wired one the other day ago i got the vertical mouse D though i tried to do as much research as possible. But that is my only gripe with wireless ones is having to replace the batteries. The last wireless i had was very long time ago and just frequently replacing the batteries is just a turnoff for me. but what do you think. is vertical mouse 4 better than vertical mouse D?

​@@ragincaucasian9209 I don't think the D is better just a bit different on the design, more of a personal choise, can't help you there :). In my expierience the evoluent, no matter what model you pick, has the best comfort mouses out there, and I tried many from logitech and others.

it was, I opened it when I got it to take a look inside