O.H.M.S.

O.H.M.S. stands for On His (or Her) Majesty's Service.

It is used as an overprint for official stamps of the British Commonwealth. It is also punched as a perfin, and is also printed on official mail and stationery.

 File:Canada 14c OHMS.jpg|Canada 14c Peace with O.H.M.S. overprint. File:Canada air OHMS perfin.jpg|Canada airmail with O.H.M.S. perfin. 

[[Category:O]]