20 C. blue with interesting perforation, value indication "20 C POSTES 20 C" at the top instead of the bottom. The stamp probably originates from the lower margin and was separated from the sheet in such a way that the perforation is complete on all sides, and the value indication actually belonging to the stamp is also present and attached below, presumably cut with scissors. As a single franking on a postal card from "LE HAVRE 20 AVRIL 67" to Paris, minimal traces of aging.