This is the OEM Exhaust Manifold Stud and nut found in the cylinder head of all VQ35DE engines.

Exhaust Stud

• Part Number: 14064-31U0C
• Price: $1.61
• Order Link: https://www.quirkparts.com/oem-parts/nissan-exhaust-manifold-stud-1406431u0c

Exhaust Nut

• Part Number: 14094-9BA0A
• Price: $1.15
• Order Link: https://www.quirkparts.com/oem-parts/nissan-mnfd-w-converter-nut-140949ba0a