Opticz UV Blacklight Reactive Large Tip Invisible Ink Marker, Blue

Invisible and works great with black lights. The longer you let it dry the less visible it is. After a few days it is quite hard to see it. Unless you have a black light. The tips are easy for kids to smash. That’s the only thing I don’t like about them. price could be a little lower.

Drew all over my walls in my house and my girlfriend loves it. Very bright and bold lighting. The tip started to fade after I was done drawing but I put the pen down for a while and it came back with full color!

Great replacement for Breakout EDU pen but still have to keep cap on tight.

Great value for the price. Exactly what I needed and doesn’t look like it will dry out too quickly. Works great on all types of materials and is invisible as advertised! Would definitely recommend!

I’ve tried a lot of these kinds of markers, and this is the only one that lasts.

It has a fairly thick line. So secret messages will have to be short. But I’m using it with kids at a camp so should work.

I really enjoy just how vibrant these markers are! And they are easy to use! I wish they didn’t run out of ink quite so fast, but keep in mind that I am working on a rough surface upside down, so the marker is not going to hold up as well as it would on typical paper. To give an idea for project size. That is about 8 hours of work and I used 3 markers.

Doesn't glow as well as the pink, but works well none the less and is invisible :)

Worked exactly as advertised!

Great product wish they made it in a thin tip but even when it is a wide bullet tip you still can;t really see the ink unless you know to look for it.

Definitely worth having to personalise valuable items at home incase of theft.

A bit pricey, but is an excellent pen that is so much better than the children’s pens being sold. This is a true professional pen that will not only last longer, but will provide a high-quality UV marker.

I’m using this for security of coupons so they can’t be duplicated, it works perfectly.