Secret Message Sweatshirt (SMS)

The SMS in this sweatshirt does not stand for short message service, but for Secret Message Sweatshirt. The SMS sweatshirt combines thermochromic ink, conductive thread, coin-cell batteries, and a hidden switch to reveal a message of the wearer’s choosing at the flip of a switch.

Tools: Thermochromic ink, low-resistance conductive thread, conductive velcro, li-on coin cell batteries, switch.