5x 3/4-16 3/4" SAE Drain Plug 5/16" Allen Nitrile Oring Sherex S08-HS-1-B08A

Oring is nitrile, so it will withstand Fuel or Oil
Brand new plug!
Specs are here:

http://fasteners.sherex.com/Asset/S08-HS-1-B08A_A.pdf