






🕵️♂️ Unlock the invisible. Write the unforgettable.
The KERRT Invisible Ink Pen set features ultra-fine 0.3mm tips with safe, flavorless ink that remains invisible until illuminated by the built-in UV light. Perfect for kids aged 8-12, these pens write on paper, skin, and fabric, making them ideal for secret messages, party favors, and classroom fun. Durable and non-toxic, each pack includes four pens powered by LR44 batteries, combining playful mystery with reliable quality.



| ASIN | B01N6N4JJR |
| Batteries | 1 LR44 batteries required. |
| Best Sellers Rank | #53,766 in Toys & Games ( See Top 100 in Toys & Games ) #41 in Toy Electronic Spy Gear |
| Brand | KERRT |
| Closure | snap |
| Color | Multicolor |
| Customer Reviews | 4.5 4.5 out of 5 stars (2,712) |
| Date First Available | January 3, 2017 |
| Grip Type | Smooth |
| Ink Color | Black |
| Is Discontinued By Manufacturer | No |
| Item Weight | 1.13 ounces |
| Item model number | CYJ10 |
| Line Size | 0.3mm |
| Manufacturer | KERRT |
| Manufacturer Part Number | CYJ10 |
| Material Type | Plastic |
| Number of Items | 4 |
| Point Type | Fine |
| Product Dimensions | 4.02 x 2.01 x 0.59 inches |
| Size | 1 Count (Pack of 4) |
C**H
Big hit with kids—and a fun throwback for adults too
I bought a bunch of these to give to a group of kids, and they were a total hit. The invisible ink and UV light bring back memories of old decoder pens—such a fun, clever concept. They’re easy to use, work well, and make a great little gift or classroom surprise.
H**Y
Excellent gift for kids
Got as a Christmas gift for my son because he’s been telling me he wants an invisible ink pen and we’ve had so much fun ever since Christmas! We even write on our hand little messages to each other and then use the glowing part to reveal the message. He has shown other children and they’re impressed by these pens as well. Parents are asking me where I got them. They’re good quality, very durable, great value for the money since you get four. They are easy to use to use and they do dry quickly.
D**S
Worth it - kids love them
Great value and color variety. The kids had so much fun using these pens. And they actually work great. Good buy
Z**A
Dries up very quickly
These pens are cute and fun to use; my kid sibling loved it. However, it dries out very, very fast. Also, we'd just been using two of these pens, and left the other two unopened for later (there are four pens in one package), but when we went to use the unopened pens a few months later, it did not seem to be working. The lights worked but the ink did not show up under the light. It's a cool product but for temporary use.
B**Y
Fun & Engaging Spy Pens - Kids Loved Them!
The KERRT Invisible Ink Pens were a big hit with the kids! They loved writing secret messages and revealing them with the UV light. Fun, easy to use, and great for parties or gifts. Highly recommend!
A**N
Great way to protect your items
love them they work perfect
P**D
Seemed fun but kids didn’t use
I am not sure if it was the product or that my grandkids just were not interested, but I got these for them for stocking stuffers and they pretty much just put them aside. Maybe it was because they were overwhelmed with other more impressive gifts. But I still have not seen them use them.
L**N
Portable black light messages
My son asked for these pens after seeing them at a book fair. He took them the same day they arrived to a football game. It was a little cold outside but the pens wrote smooth for the entire game. No one had any idea was he was writing down until he used the black light that's attached to the cap of the pen. He loves that he can write secret messages and I love that he's practicing his writing skills so it's a win / win. The four pens glow in the same color so the pen color is not an indication of ink glow color. All the inks are clear and you need the Black light that's attached to the cap of wach pen to see the message. This was the best deal I came across for this type of pen. My toddler also lost the cap after stealing it from his brother's room and after 2 hours without a cap it still writes.
A**T
I bought these as a replacement for one we got at the scholastic book fair. These are a great comparison to those ones and work just as well!
E**.
Used the pens to write invisible clues for a Christmas themed scavenger hunt I prepared for my grandkids. Their little minds were blown once they saw how they worked. Fun was had by all. LOL: After the scavenger hunt; the grandkids may or may not have written invisible scatalogical words on their parents hands and arms.
L**E
These guys do exactly as advertised-I secretly use them daily...XD. They are also cute, and the light on each pen is very helpful.
A**R
Very good
C**S
Super fun
Trustpilot
1 month ago
1 month ago