He-Man, like Batman had a "Bat Signal," and the Widgets had the privilege.

Whenever the Widgets are in trouble and their fortress is threatened they need only do one thing; fire the signal flare and call He-Man! If this reminds you of the "Bat signal" from the Batman series, you would be right in thinking so. The signal flare lights up the sky with an image of the symbol that appears on He-Man's harness. Fortunately every time they fired the flare, He-Man just happened to see it.

MU12 - "Evil-Lyn's Plot"
The four-sided shape on He-Man's harness is given some much-needed attention in this episode. He-Man reveals that the harness was fashioned from Coridite; also we see for the first time how the Widgets contact He-Man when they are in trouble. The Widgets' symbol for He-Man is the same as the one as his chest, actually giving some meaning to the shape.

MU91 - Jacob and the Widgets
Knowing Mer-Man has gone into the mines to get the Coridite, Cando unleashes the flare hoping for the best. Normally there is some kind of realistic delay between the signal firing and Adam's sighting, but Harvey Brenner puts the two incidents back-to-back in such rapid-fire timing that it becomes funny. Right after Cando fires the cannon, the camera cuts to a shot of Adam and Cringer. The scene is so painfully obvious we cannot help but laugh. It is amusing to watch a He-Man writer finally making fun of the Widgets' flare formula. The He-Man signal looks great this time, because instead of it being typically head on, it is at an angle.

MU92 - The Littlest Giant
Much is made of the Widgets' flare in this episode, perhaps more so than in any other. Usually it is regarded as a measure to be employed only in extreme circumstances, but this time the Widgets use it twice in one act. In both instances, Prince Adam is the one to spot the flare, so this necessitates two transformation sequences in Act One. The first time, Adam and Orko are alone in the forest for no apparent reason, a situation quite similar to Adam and Cringer's sighting of the flare in "Evil-Lyn's Plot."

Later, it is Adam and Cringer that see the second flare. This time, Adam appears ready for bed as he is in his nightshirt watching out the window.

Even though the Widgets appear in the other episodes, they do not fire the signal flare on screen. In "The Mystery of Man-E-Faces" we actually see Man-E-Faces destroy the mechanism just as they are about to fire it; "Into the Abyss" has He-Man, Teela and Orko already helping out the Widgets, and in "The Gambler" the Widgets are already part of the episode.

The first time we see the signal flare mechanism is in "Evil Lyn's plot." It is the design that is used again in season two's "The Littlest Giant."

The second time we see it is in "The Mystery of Man-E-Faces." Now this story is told in flashback, so we can only presume that the reason this mechanism is a different design is because this flashback takes place before events in "Evil Lyn's plot."

So after Man-E-Faces wrecked this one, they created the one seen in other episodes.

And finally in "The Littlest Giant" we see the signal flare mechanism for the last time.