A back up feature in the Charlton Comics comic book Thunderbolt, starting in issue #54 (Oct. 1966). This small-time folk trio become superheroes when dying Russian scientist Dr. Kolotov bestows his inventions on them, making them the superhero team The Sensational Sentinels. Written by Gary Frierich and drawn by Sam Grainger.
Lineup: Rick Strong (Helio), Cindy Carson (Mentalia), and Crunch Wilson (Brute).
They were short-lived, and only appeared in issues #54-59.