Im in the process of taking off my exhaust manifolds and came across the flange. Well they are weird looking almost looks like a circle. As if someone just burrowed a circle out. Im sure these are stock screws. All I need to know i what tool do I use to get them off or how to get them off pics would be great or you can just tell me idc.

But this is urgent working on my car right now and running out of day time. not like that is going to stop me but id rather not work at night. If anyone knows anything about this just respond quickly even if its a single word I'm ok with it as long as it helps.

Thank you

 

Solved: new to this, found out there is a nut underneath. all good now thanks anyway