What's this and why did I find it laying next to the radiator?

[AuH2O]

Found this little hard plastic thing laying at the bottom left of the radiator on my '88 K5, and I don't know what it is! It measures about 3"x1.4"x1". Some kind of bracket for the radiator? Certainly not a bushing? All I know is it's meant to hold something in place... Does anyone know?

http://img214.imageshack.us/img214/8910/radiatorcf7.jpg

 

[ryoken]

It's a factory battery holddown... screwed down, pinches the one side of the battery...

 

[AuH2O]

Aaah, thanks... That might explain why the PO put a cargo strap around the battery - thinking he had lost the damn piece.