What size screw for the cooling fan cover?

[drawkward]

I got this replacement cover from Reign. To my surprise it came with little screw threads. I was wondering if someone might know what size these screws would be, so I don't have to take it off in the parking lot and walk into Lowes with it... I'm going to be doing the custom fan scoop mod from the tech section this coming monday or tuesday. I thought it might be easier, for me, to utilize the little screw holes that were already there. Might make things a little quicker too.

[90GTVert]

That might be a tough one. I know the hardware stores around here don't really carry much below 5mm, and those are smaller than that.