The Kensington Orbit Wireless Mobile Trackball offers a precise compact and versatile experience with a centered-ball design. With no wires to tie you down the 2.4 GHz wireless with storable nano receiver works wherever you do at your home or office. And the unique touch scrolling lets you glide effortlessly through web pages and documents.- Unique touch scrolling lets you glide effortlessly through web pages and documents- Professional matt black high gloss black finish- Compatible with Windows7 Windows XP Windows Vista and Mac OS X. TrackballWorks software downloadable from www.kensington.com- Two customizable buttons with Kensington TrackballWorks software- Secure 2.4Ghz wireless technology reduces risk of interference and is ideal for office environments- Ambidextrous design for left or right-handed users- USB Plug & Play- A distinctive centered-ball design gives you more comfort and precision- Nano Wireless USB reciever stores inside mouse battery compartment when travelling- Requires 2 x AA batteries (included)- On/Off switch helps prevent accidental battery drain