sr20det flywheel bolts

I have the 12 point flywheel bolts. What size are they and what is the socket called I buy to take these off? Ive heard them called caterpillar bolts but beyond that Im not sure. I bought one socket that was suppose to work but because the bolt head was so shallow the socket wouldnt grip propperly.

Eh normal socket takes it off. Different brands have different slopes so go buy a different brand