Made in Japan,December 1983 production OC-2, still "Octaver" model,lighter brown paint, short dash, black screw & black label. Still considered by many to be the best of the BOSS OC series, for both sound & tracking.

from bossarea.com
The OC-2 had originally a much lighter non-metallic brown colour and it was labeled "Octaver" instead of Octave. The name changed early 1984 while the darker shade of brown was introduced about a year later.