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From the item details page:
Packed with cutting edge technology, this industry-leading wireless gaming mouse puts precision and total control in the palm of your hand
Sink your fangs into the game armed with the ultra-precise Viper Ultimate gaming mouse. This lethal predator comes packed with cutting-edge technology, like ultra-fast Razer HyperSpeed Wireless transmission and a new-and-improved sensor that tracks even the finest movements with deadly precision.
Add in an industry-leading optical switch for lightning-fast actuation and a durable, lightweight form factor and you’ll be in total control to dominate the digital battlefield.
Dimensions 126.70 × 66.20 × 37.80 mm
Weight 0.07 kg
Battery Approximately 70 hours (without lighting)*
*Battery life varies by configuration, operating conditions and other factors. Maximum battery capacity decreases with time and use.