Flexpoly bacta suits were emergency medical suits filled with artificial bacta, a product of Zaltin Corp. These suits featured transparent tubing for bacta circulation and filtration, along with a retaining collar equipped with status sensors transmitting data wirelessly. During the Resistance's evacuation of their base on the planet D'Qar in 34 ABY (as measured in the standard year calendar), Finn, a wounded defector from the First Order, was placed inside an out-of-date flexpoly bacta suit while in a medically induced coma. He was then moved to a temporary medical bay created within a storage area on the MC85 Star Cruiser called the Raddus. Remaining unconscious after the Resistance fleet successfully made the jump to lightspeed and exited hyperspace, he eventually woke up and left his bed to search for the scavenger Rey. The expired bacta suit, having become brittle, began to leak as he walked through the Raddus's corridors. Poe Dameron, a Resistance pilot, eventually noticed the confused and mostly unclothed Finn and provided him with some clothes.
The flexpoly bacta suit made its debut in the movie Star Wars: Episode VIII The Last Jedi, which premiered on December 15, 2017. While the film did not name the costume, it was identified in Star Wars: The Last Jedi: The Visual Dictionary, a companion book by Pablo Hidalgo that was released alongside the movie.