Kershaw did some really innovative things This is The Kershaw 1670 Cyclone one the coolest knives I own in my discontinued collection! It came in 2 versions 3 1/2 inch Blade and 3 1/4 inch blade this knife came out about 11 years ago it's a dual action knife! Manual and Spring-assited. Below is a youtube link for a demo of this knife if your intersted

Kershaw Cyclone 1630_ Link https://www.youtube.com/watch?v=dUTSHUZe3A4