Self defense keys and keychain, made for my wife after a co-worker was harassed and assaulted downtown. Meant for self-defense only. Don't be a victim! Use common sense, do not take where such items are prohibited. By downloading this you accept any liability and responsibility. Non-lethal but will definitely deter an attacker. Blank insert F3D file included for customization. For best results print at 25 - 50% infill, preferably triangular for better strength and rigidity. Insert pieces are press-fit, so be sure your filament is properly dried and use the correct temperature for your type of filament. Works best with PLA, PLA+, CF PLA or ABS. Inserts can be pretty much any type of filament you like. Reuse any old keychain ring, as long as it's not too small.