MAF sensor cover? why is it there and what does it do?

I just replaced my MAF sensor and I didn't know that it had a removable metal outer cover over it.

I found out it had a removable cover when I accidentally dropped the old one and the cover just popped off.

there was no glue or anything to indicate it should be permanently attached to the old MAF sensor, so I put the cover back on over the new MAF sensor the same way it just sat on top of the old one figuring it has to be there for a reason and must serve "some" purpose but I still would like to know why and what does it do?

also as a side note if someone wants to know the part number for their MAF sensor its under this metal cover in big huge bold letters but until you take off the cover you cant see anything but a very faint engraved number impression on the cover if you can even read it.

the part number on my MAF sensor cover is 22224-75020 and the part number for my MAF sensor by itself is 22224-75010 so I guess this is why replacement MAF sensors always list both numbers together as the part number they replace.

does anyone know and can explain this MAF sensor cover?

 

this is what one looks like without the cover on it: http://www.ebay.com/itm/Toyota-Lexu...Parts_Accessories&hash=item43d70d779e&vxp=mtr

and this one still has the metal cover on it: http://www.ebay.com/itm/97-98-99-00...Parts_Accessories&hash=item3aa58d5c4f&vxp=mtr

 

Load spreader. Us peasant parts replacers were cranking the screws down to tight and popping sensors.

Sounds good,,right?.

Go with it, if you choose. Otherwise,,another unnanounce evil changeup on the assy line is probably a little closer to target.

The bottom sealing cover popped off of mine when I serviced it the other day. A few tack dabs of sealer adhesive to hold that plate in alignment, back in it went a day or so later.

 

mine never had that metal cover on it. came the normal way from the factory

 

I just figured maybe it was some kind of a heat shield protection or something?

I just cant see what purpose it serves at all