The Rollock is a very slick knife from CRKT. To open the knife, you simply press down on the spine of the blade to raise the point. Then you push it forward until the lock engages the blade in place. To close the knife, simply press on the upside down lock back, grab the blade and slide it back, then pull against the spring until the blade snaps into place.
It sounds confusing, but with a bit of practice, you'll grow to love this neat mechanism. This model has a blue translucent composite handle and partially serrated blade. Includes pocket clip.