These Use a 5/16” Allen Wrench/Socket.
BBK 1577 fits Ford SBF 302 351W Exhaust Header Bolt Kit - 3/8-16 0.75in (16)
ARP Auto Racing 100-1107 - Exhaust Header Bolt
ARP Auto Racing 400-1102 - Exhaust Header Bolt
Chevy BB 12 Point 3/4" Black Oxide 170K PSI Exhaust Header Bolt Kit 16 Pcs. NEW
Chevy BB 396 - 427 12 Point Black Oxide Gr 8 Exhaust Header Bolt Kit 1" Long NEW
ARP #140-1101 Exhaust Header Bolt Kit Chrysler 5.7L/6.1L Hemi
