A fun gift, budding secret agents can use these 2 pens to write messages which can only be seen under the pen's UV light.
- Step 1: Write a secret message
- Step 2: Use the secret lamp in the pen lid to read the message
Each pen uses 3 LR41 Lithium batteries which can be replaced by unscrewing the pen lid. Remove the white caps from the pen nibs before using for the first time