These permanent UV Markers leave just a clear (invisible) mark under ordinary light. Under UV light (blacklight) though, the writing is plainly seen, and appears blue. Writes on any surface. Ideal for all security uses. Great for writing secret notes that only someone else with a UV light can see. Ideal for marking your Stereo, TV or other valuables. These are permanent markers and will write on pretty much everything.... metal, plastic, paper, etc.
Package of one.