The Evoluent VerticalMouse was evaluated at UC Berkeley by a team of medical professionals, including physical therapists and ergonomists. The VerticalMouse was found to be comfortable and easily adapted to, promoting a neutral wrist and forearm posture. Your arm is aligned in a natural position providing an unrivaled comfort experience and preventing weariness and other problems usually coming along with the use of traditional mice. The VerticalMouse is considered to be the reference vertical mouse in the market, and has already satisfied thousands of clients throughout the world.

Evoluent made the following changes between the VerticalMouse 3 to the VerticalMouse 4.
· Improved thumb rest. The thumb rest has been reshaped to provide even more comfort over earlier versions.
· Now two thumb buttons. A new bottom thumb button provides greatly extended functionality when used with the included driver.
· Extended lip prevents rubbing. An extra wide lip along the bottom edge prevents the last finger from rubbing the desk.
· Adjustable laser sensor. Pointer speed controls on the side allow convenient adjustment without even releasing your grip from the mouse.
· Pointer speed indicators. Top mounted LEDs show through the chrome thumb rest to indicate selected pointer speed including extra low (XL), low (LO), medium (MD), to high (HI).
· Lighted Evoluent logo. The logo is pure eye candy. The illumination turns off when the system is in sleep mode to conserve notebook battery power.

Guarantees
· 100% money-back guarantee including shipment cost for 60 days
· Quick shipping
· 1 year manufacturer warranty
· Dioxide emissions off-setting

Advantages
· Eliminates arm twisting. The patented shape supports your hand in a fully upright handshake position that eliminates forearm twisting. Many users said that the mouse relieved their hand, wrist, or arm pain.
· High quality grip and manufacturing. The mouse grip is comfortable and efficient. The mouse is built to last, with quality materials and great finish.
· Easy to use buttons. All 6 buttons are easily operable without contorting your fingers. The button force is light for easy clicking, but still firm enough to avoid accidental actuation.
· Fits different size hands. The new shape fits larger hands as well as smaller hands better.
· Prevents desk rubbing. A lip on the bottom edge prevents the little finger from rubbing the desk.
· Precision tracking. High quality optical sensor tracks better than many laser mice so you don't waste time chasing the pointer. The adjustable 800 to 2400 dpi true hardware resolution moves the pointer more quickly to reduce hand movements.
· Programmable buttons. 6 buttons are each programmable with different functions in different applications. For example, a button can be Double Click in one application and Ctrl in another application. The software provided with the mouse also includes several functions such as : Speed toggle - cycle among up to 3 pointer speed settings with a keyboard shortcut or mouse button. Auto click - automatically perform a single or double click by pausing the pointer. Adjustable time delay for activation."