These UV ink markers are completely invisible in normal lighting, but illuminate incredibly bright under UV blacklight! Use these ink markers to implement security procedures, secretly mark your valuables, write hidden messages, artistic application, or just for plain fun! Each marker is full of our special blend of UV ink, so you get long lasting UV special effects.
Product Features
- Ink is completely invisible in normal light; very bright under blacklighted conditions
- Full sized Marker
- Precision fine point tip
- Alcohol based ink; dries quickly
- Does not wash off easily
Secret Squirrel pens are fun and useful! Secret spy pens. Kids will love them. Some paper it bleeds through and you can kinda see some colors when held at the right angle in the sun. But as far as for fun or hiding passwords or something like that, its spot on. The yellow seems to be the best of the three in not showing up on the paper, but if this is for fun or for the kiddos, its really worth it. Marking cards for magic tricks? Yea you could. Marking belongings to the teacher in a classroom to prevent theft? You could totally…
Red is bright – the others are not as effective
Didn’t work on colored pictures- only white paper