Wow, a doll onesie from the 80s! This grey men's outfit was from the Sergio Valente line of dolls and fashions that were released in 1983. It has a burdundy and yellow stripe and "Sergio Valente" written across the front. The back has a zipper enclosure. The Sergio Valente dolls were 12 inches in height, so this outfit would also fit your Ken doll. This onesie is in very good condition, but has few stains on the front.