This TR-4 is from the Pro-Tech Operator Series, with the all black finish, no logos, and a tritium vial in the push button. The TR-4 features a 4" black finished CPM-D2 steel blade with a plain edge. The ergonomic handle is black anodized T6 aluminum. The TR-4 is a knife that will not let you down. It fires hard, locks up like a rock (what else would you expect from Pro-Tech?) and feel great. The TR-4 has a pocket clip (tip up) on the back of the knife for easy carry.