This is a brass exhaust system "high-nut" for a variety of Fiat and Lancia cars.
3 times taller than a standard sized nut for maximum grip, and brass for superior life in high-temperature environments.
Will not seize onto steel studs or deteriorate like a typical steel nut. Use on exhaust manifold studs, collar studs, catalytic convertor slip joints, etc.
New and unused.