Are you looking for a better way to write your secret messages? How about going invisible!
For those of you who like the secret agent approach to geocaching, we offer the Ultraviolet Felt-tip Marker from our friends at Markal. This marker produces an ink that is invisible under normal light, but glows brightly under a UV or black light!
For those of you who like the secret agent approach to geocaching, we offer the Ultraviolet Felt-tip Marker from our friends at Markal. This marker produces an ink that is invisible under normal light, but glows brightly under a UV or black light!