The Solid Force Field Cageis a device that features in He-Man and the Masters of the Universe.
Invented by Skeletor, the Solid Force Field Cage was a clever way to cage prisoners while to make them do his bidding. Man-At-Arms was once held in a Solid force Field Cage after being captured by Trap Jaw. The Evil Warriors were aware of Man-At-Arms' great skills in inventing technology and aimed to force him to work for them.