Great Britain 1941 2d. pale orange. IMPRIMATUR. BLOCK OF 8 WITH CENTRE BLOCK OF 4 BEING ‘TETE-BECHE’. Released from the National Postal Museum Archives. Handstamped on reverse, ‘NP IMPRIMATUR’. The Imprimatur sheet was sent directly to the National Postal Museum for their Archives. THIS BLOCK IS FROM THE SINGLE SHEET PRODUCED AND IS UNIQUE. Superb unmounted mint condition. OUTSTANDING AND EXCEEDINGLY RARE. AN EXHIBITION PIECE.