The Spam Fritter Butty is battered and fried Spam on bread; chip shop item.
It sits within the Submarine Sandwiches family of French sandwiches — specifically the The Fish Finger Sandwich & Chip-Shop Butty cluster, which gathers the regional and stylistic variants that share its frame.
For the broader The Fish Finger Sandwich & Chip-Shop Butty tradition that frames this sandwich, see The Fish Finger Sandwich & Chip-Shop Butty.