Detecta Mark Anti-Theft Set

The Detecta Mark Anti-Theft Set includes 2 pens that write with permanent, invisible ink which can only be seen under ultraviolet (UV) light and a stylish UV pen light. With this set you can mark your valuables with the UV pen that police can use for identification if stolen and recovered. It can also be used to check for counterfeit money or as a spy toy for children to write secret messages. The UV flashlight measures 5 inches long and requires 3 LR-41 batteries (included, along with an extra set of 3).