UV marker

UV marker with UV led lamp
UV marker with UV led lamp

An ultraviolet (UV) marker is a pen whose marks are fluorescent but transparent; the marks can be seen only under an ultraviolet light. They are commonly used in security situations to identify belongings or to prevent the reproduction of unauthorized banknotes. UV pens can now be bought at some stationery shops to securely mark items of high value in case of theft.[1]

  1. ^ "History of Invisible Ink - The Art of Manliness". 9 September 2011.