Leaflet

n.
  1. A little leaf.
  2. (Bot.) One of the divisions of a compound leaf; a foliole.
  3. (Zoöl.) A leaflike organ or part; as, a leaflet of the gills of fishes.
  4. A printed sheet of paper, of one page, or one sheet folded over, containing an advertisement, tract, or other notice, and usually distributed for free or included in the package with a purchased item.