细节
cover 1928 "ON POST & TELEGRAPH SERVICE" XU5 (official crest on reverse) registered from Bangkok (9.3) to Kuching, Sarawak (19.3 arrival) via Penang (12.3) and Singapore (14.3) bearing 15s. pair cancelled by c.d.s., with red wax seals on reverse inscribed "FC" (Finance Department - very rare).