A UV pen and light in one convenient tool. Making use of ultraviolet light can be an excellent way to do stages of a multi, leave clues to a puzzle or a great addition to a night cache.
Each spy pen features ink that is made of special high-brightness compounds that are invisible to the naked eye, but magically illuminate when exposed to ultraviolet light. A blacklight is conveniently located on the opposite end of the pen making this perfect both for geocachers who want to build geocaches with a "UV Light Required" attribute or for those who want to find them!
Length 5" or 12.8cm