This mouse if first and foremost intended for gaming. The side buttons help you use the mouse a bit more efficiently.
From Amazon
Razer Naga V2 HyperSpeed - Ergonomic Wireless MMO Gaming Mouse (with 19 Programmable Buttons, HyperSpeed Wireless (2.4 GHz), Up to 250 Hours of Battery Life, Focus Pro 30 K Optical Sensor) Black
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