Type IC2
Purple Censor Mark 
With Vermilion Personal Seal

UNLISTED FIELDPOST
CENSOR MARK

Similar to Davao City
Type IC2 Censor Mark

Top red boxed-in four kanji
characters denote
"Gunji Yubin" or "Military Mail".
Bottom red boxed-in kanji
characters denote
"KoYo" or "Official Mail".

Official army military mail from the Philippine Archipelago,
Philippine Department of Administration, Lanao State Office
to the Philippine Department
of Administration, Director of Provinces, Manila.