The CRKT M21 has been designed by Carson with features as requested by the military. You will be able to get it with a deep bellied spear which is able to provide you with maximum strength and also two Carson flippers for easy opening. It is very easy and simple to open the knife. By applying a slight pressure to the flippers with your wrist at the same time the blade is out and ready for action. On opening the blade, you are assured that you are holding a knife of substance.