If you utilize LED gentle on the cap to shine on it, you will see the phrases. Enjoyable to make use of. Do contemporary intelligence agencies use UV-sensitive invisible ink? The ink exhibits solely when exposed to gentle; write on paper or wooden with confidence. I originally ordered the black paper to jot down on, but you cannot the ink on black or yellow or orange, I think – I tried several colors but forgot to write down which ones did not work right. Open