This is the Kershaw NRG, model 1740. This knife has an extended tang in the back that can be used to flip it open quickly. As a matter of fact if you flick your wrist while pulling the tang the NRG will fly open in a hurry. The Kershaw NRG is a very well built knife, even without the featured tang. It opens smoothly, has a great grip, and of course it comes shaving sharp!
Kershaw 1740 Technical Specs: