And stocking stuffers should ideally cost below $20, so at just $8 for a six-pack, this set definitely fits the bill. Invisible ink pens are just as cool now as they were when we were kids.

"The pen set has brought a whole new level of fun ... especially during playdates and rainy days indoors" Their one note? "The invisible ink works best on plain white paper or light-colored ...

Pack of 24 Invisible Ink Pen and Notebook - This top secret UV pen set includes 24 spy pens and 24 mini notebooks. The invisible ink pens have 8 colors to choose from: blue, black, red ...

The SCStyle Invisible Ink Pen set is a perfect gift for large groups of children. Other invisible ink pen products may have designs, ultraviolet lights or ink hues that better fit the specific ...

And stocking stuffers should ideally cost below $20, so at just $8 for a six-pack, this set definitely fits the bill. With over 6,300 five-star ratings from Amazon customers, the Maleden Invisible Ink ...

"I bought the Maleden Invisible Ink Pens for my four grandkids and they all love to use them to write secret messages," wrote another five-star reviewer. "I have to admit, at 66 years old I kinda like ...