Postal Mechanization in the USSR
(cont)
The type of level start bars, Hsh-3, was introduced in 1973, and remained in effect through th eend of the Soviet Union. The airmail rate was 6 kopeek and the ordinary rate was 4 kopeek.
Front of airmail envelope with instructions under index boxes - rubric B.2
Back flap with instructions - rubric A.3
Back of envelope information
From front of envelope - instructions to sended, rubric C.3