Oatey Mushroom Vent Cap, 3 Pack

Can it be used for a 2” dwv stack? Need to prevent rodents.

What are the specs on the hex bolts? I will be using these to drive a wind powered whirligig.

I need to install on 2" vents- what exact hex bolt 2" long should I order to use-- what exact size ?

How do these for both a 3" and 4" pipe?