Hi!
It's a 1/4 scale "Midget Mustang" wing (span 165cm). I bought some of these 1/4 scale pylonracers (Rivets, Midget Mustang, Little Toni, Shoestring etc) from a small company (Quay Baber Models) in Ohio 12 years ago, who specialized in making glass fiber 1/4 scale pylonracers. But the founder died and the company seized.

Regards!
Jan K
Sweden