It's been modified. Commonly called a "Sawed Off" shotgun, it's been pretty much butchered and may be illegal.
Measure the barrels by dropping a dowel down the muzzle until it touches the breech and can't go further. Mark the dowel, withdraw and measure. If it's less than 18", it's illegal by Federal law.
if the OA length is less than 26", same deal.
If both lengths are OK, it's just useless.