M8 x 1.25 exhaust manifold copper flashed nuts available, see Part Nos. 35412 (13mm Hex, 10pc), 31564 (13mm Hex, 50pc), 30736 (slotted lock 12mm Hex, 5pc), 30739 (flanged 13mm Hex), 30737 (self locking, flanged 12mm Hex, 5pc), 30742 (self locking, flanged 10mm Hex, 5pc) and 30741 (self locking, flanged 13mm Hex, 5pc).