Positive battery bolt size?

[flnycus]

hey all. being the noob I am, I was removing the battery and the nut that fastens the positive terminal to the battery fell. Anyone know what size this is? is it a special nut or can I just try n get one from home depot or AutoZone? I haven't been able to find it yet. thanks.

 

[Imperial4runner]

Pretty sure its a size 12

 

[TechWrench]

If you are having trouble finding the correct nut to fit the bolt you have, then just buy a new matching set. It doesn't matter if they are sae or metric, as long as they tighten up the clamp.