LAIX Portable B2 Self Defense Tactical Survival Pen Aviation Aluminum Multi-function Outdoor Camping Tool This pen is made of aviation aluminum with high quality. It's suitable for self-defense, handwriting signature, gifts, escape off the car. 5.83 inches overall length, weighs 1.65 ounces. Made of aviation aluminum, high quality. The design is simple but fashionable, comfortable for use. Not only is a writing pen, but also a good tool for self-defense