Pistol Kanji
From Halopedia, the Halo wiki
Hidden on the Pistol are two Kanji (Japanese) characters. The first, on the top of the gun, is the number seven (七, shichi/nana in Japanese, qi/tsat in Chinese). Bungie enjoys using this number as often as possible. The second, found on the butt of the gun, is the character meaning "power" or "strength" (力, chikara in Japanese, li in Chinese).