Tarantula Purple Fully Automatic Out The Front Knife. The blade on this Tarantula is double sharp on both sides with black and silver which has a bite like a beast. These fierce knives are more intimidating than most others. The blades are stainless steel, spear point. These knives are fully automatic. Push the button up and the blade bolts into action. When the button is pushed down the blade returns to it's closed position. Each knife has a black pocket clip included so you can secure your knives into a comfortable position. overall length 9 inches 440 stainless steel