Optical Mouse. 

<br/><br/> A4 Tech Optical Mouse (OP-720)<br/><br/>Features:<br/>1. Optical Sensor - Accurate Tracking<br/>2. 8-in-One Gesture - Selectable Commands<br/>3. Symmetric Fit - Comfortable Design<br/>4. 1200 DPI - High Resolution<br/>5. 4-Way Smart Wheel - Enhanced with Driver<br/>6. Teflon Foot - Works on Most Surfaces<br/>7. 5M Clicks Lifecycle - Extreme Quality<br/>8. Dust-Resistant Wheel - Prolong Wheel Life-Span<br/>9. Plug & Play - USB Port 
<br/><br/><label>Dewey Class. No.: </label>AV Optical Mouse #1