The gun shaped house key is a blank key that you can get duplicated to use as your house key, and will more than likely get you tazed, arrested, and labeled a terrorist if you ever brought it to the airport. This particular gun key is a 45 caliber gun key, but if you are picky about your guns there are a plethora of other gun key designs such as a rifle key, cowboy gun key, or a revolver gun key. The 45 caliber gun key will fit all shlage type of lock designs and is a great way to know what key is for your gun safe.