1978 United Kingdom, "Thermos" Sticker Sheet (32 stickers).
This is actually a sticker sheet, with 18 square stickers and 14 more (small) rectangular stickers. These were meant to be stuck on a lunchbox, a "Design Your own Star Wars Lunch" kit from Thermos.
The scans below are the top and bottom of the large sticker sheet, and the original lunchbox kit. The small print indicates the year as 1978.
WANTS FROM THIS SET: None.
