This Belgian 5 Francs stamp features a beautifully detailed illustration of the Boomklever (Sitta europaea), known in English as the Eurasian Nuthatch. The artwork captures the bird’s distinctive blue-grey plumage and chestnut underparts as it clings to a tree trunk, highlighting its natural agility. Issued by Belgium (België–Belgique), this stamp is part of a definitive wildlife series showcasing native bird species. It reflects Belgium’s commitment to environmental themes and fine naturalist engraving during the late 20th century.