[DELUX Ergo Vertical Series Mouse] ?
It is important to equip with the correct size vertical mouse, which let you easily get used to the use of vertical mouse, and more help dramatically comfort hands muscle.
Every people have different hand size and there is no one size fitting all. Do not worry, you could find your correct size vertical mouse with DELUX Ergo Vertical Series, even for left handed person.
There are Ergo L(large size), Ergo M(Medium size), Ergo S(Small size) and Ergo Left(Left handed) series mouse for you. Just find your correct one according to your Palm size.