Paper folder (15 x 11 cm.) containing a foam-padded compartment with a plastic window, through which is visible an enlarged colored map of Charleroi, Belgium, and a clear plastic tube. Printed on the item are instructions for use, a colored map of Belgium including Charleroi showing "nanoparticles" on April 1, and a graph depicting "atmospheric concentration of nanoparticles" on the first day of each month. Issued in resealable plastic bag.