The “cage insert” is an aerosol delivery unit designed to be placed into a standard polycarbonate cage for animal exposures.

The aerosol is introduced into the cyclone-type top and distributed through a fine, mesh, perforated screen. Aerosol distributions of aerodynamic diameters with a mean diameter of 3 micrometers have been tested for distribution and found to be within 10% of the mean concentration for six locations in the cage. Flow rates for the tests were 2.5 LPM. Smaller sizes and larger flow rates were shown to give better distributions.

The units are made of aluminum and are hard anodized for corrosion resistance.