Patent ID: 7665419

Claim:
A rodent containment cage cover comprising: an air supply aperture in a top surface of the cover; an air exhaust aperture in a top surface of the cover; a thickness of 0.01 inches to 0.03 inches; at least one corner or edge which is configured to be present in an interior of a cage when the cover is affixed to a cage base, which is configured to be accessible to a rodent that can be contained in a cage when the cover is affixed to a cage base, and which is defined by surfaces having an angle α greater than 180 degrees and less than 360 degrees, wherein all corners or edges of the cover which are configured to be present in an interior of a cage when the cover is affixed to a cage base, which are configured to be accessible to a rodent that can be contained in a cage when the cover is affixed to a cage base and which are defined by surfaces having said angle α measured in a cage interior, have a minimum radius φ with φ=0.25/(tan((Π/360)(360−α))) inches.