France 1856 20c Napoleon Rouletted Block on Cover Nantes to Rennes

Cover franked with 20c blue Napoleon, Type I, block of four, rouletted, pleasing fresh color, tied by 2221 "Petit Chiffres" of Nantes, with corresponding c.d.s. (19 Jan), to Rennes, with c.d.s. arrival backstamp (29 Jan), Angers transit, cover folded at bottom and right, a rare franking. (Yvert 14A)