Puma Knives 6503532 SGB Bobcat Knife with Finger Groove Black Wood Handles SGB German Blade Bobcat Flip Knives. To open, just grip the knife tightly and apply a small amount of pressure on the blade power tab and with a quick snap of the wrist, the blade will open and lock into place. These knives are easy to open with one hand. Each PUMA SGB knife is made with 440A German steel for extended blade life and each blade is individually tested to ensure hardness between 55 and 57 and bears the dot of a Rockwell proof mark.