Mitsubishi A5M1 & A5M2a "Claude"

Although the tail markings are censored the photo most probably shows three "Claudes" belonging to the 13Kokutai around September 10, 1937 when the unit advanced to Kunda airfield in the suburbs of Shanghai. The aircraft on the left is a Type 96 Carrier Fighter Model 2-1 or Mitsubishi A5M2a sporting probably 2-tone brown and dark green black camouflage, while the one on the right is a Type 96 Model 1 or A5M1 without any camo, overall silver with a red tail. 

The tail marking of the unit at that time was "T-XXX" which changed to "4-XXX" a month later.

The red tail called "hoantosho" (lit: safety paint) was adopted by the IJNAF from June 5, 1933 as a measure to make the aircraft easily spotted when on water during emergency landings etc. It was gradually deleted on camouflaged combat aircraft during the Sino-Japanese War but was retained on aircraft serving on the mainland. It was officially abolished around March 1942 although it had been stopped to be applied as early as 1939.