This is a pretty rare late war item, a bottle and cup set made in the style of Bizen-yaki, which is a famous kiln for making unglazed pottery in Western Japan. The words on the bottle are "Military Colors Reception Commemoration" and the words "Showa 17th year September 27th" and "Chubu 48th Unit". The bottle comes with matching cup, and the words on the cup are the same as the bottle, minus the date. It's pretty rare to find items from 1942 or later, when the war starts going south. The unit should be a home-defense unit - the homefront reserve/detachment of a regular regiment, in this case I believe the 54th based in Okayama. There's a maker's mark near the base of the bottle with the name of the kiln and the stamp "Bizen". 

Condition: Mint

Size: 5.5" tall x 2" wide, and the cup is 2" wide