Daemson Invisible Ink Pen, Spy Pen with 9 PCS Mini UV LED Keychain Flashlight, Disappearing Ink Magic Pens with Black Light Markers for Secret Notes, Fit for Christmas Halloween Holiday Gifts (9 PCS)

I used these for a DIY escape room I put together for a team building activity. They worked great.

I use these to create secret scolls and maps for my DnD game, adds a nice dimension of realism.

Fades a little bit, but works pretty good! Now I can write secret messages in my journal.. not very bright when in natural light, but pretty vibrant when it's dark. (As shown in the second image, taken during the daytime)

Depending on what its written on, it dries completely invisible! The blue and yellow show right away when drawn under UV light while the pink draws clear and fades into a bright florescent pink! I wonder what the chemical reaction for that is.Everything came in working order from the pens to the lights, though i bought a bigger UV flashlight seperately. This isnt a flaw, especially cause i dont know what these are made of, but the pens *do not mix* - again, not a flaw in themselves, but dont expect to try to mix color combos! They do draw over eachother without ruining/smuding tips tho!

Used these for an at home escape room I made for the family. Worked great and the kids had a blast finding the hidden clues with the light. Would recommend.