Most listings use 100% polyester. Some specifically call out a faux sherling (faux shearling) fabric for a softer, cozier feel.
Many costumes use a front zipper for easy dressing. Some listings note a ring-snap zipper chin guard (a fabric flap with snaps) to protect the chin area when the zipper is closed.
Typical care directions are hand wash cold and line dry. A few listings add do not bleach, cool iron if needed, and do not dry clean.
Common styles include one-piece coveralls, jumpsuits, and bodysuit-style costumes, often marketed as cosplay or dress-up outfits with hoods or removable headpieces.
Listings consistently note that no batteries are required. Some products also mention zipper-area details such as a ring-snap zipper chin guard for added protection around the neck and chin.