Size Chart

 cm -------Uk------- US

54 -- 6 5/8 -- 6 3/4

55 -- 6 3/4 -- 6 7/8

56 -- 6 7/8 --    7

57 --     7    -- 7 1/8

58 -- 7 1/8 -- 7 1/4

59 -- 7 1/4 -- 7 3/8

60 -- 7 3/8 -- 7 1/2

Date Code

K 1968
Z 1969
M 1970
X 1971
B 1972
L 1973 (1987)
O 1974
S 1975
R 1976
A 1977
U 1978
F 1979
E 1980
G 1981
I 1982
C 1983
H 1984
T 1985
P 1986
L 1987 (1973)
Y 1988
N 1989
D 1990

Luftsreitkrafte-Air Force. 
General's  Hat cockades and yellow cap cord,
Air Force Officer, gabardine fabric, single piece cockade and silver cap cord , blue piping. Size 55 and dated "Y" (1988).
Air Defence Officer, gabardine fabric, single piece cockade and silver cap cord , blue piping. Size 56 and dated "L" (1987).
Female beret, wool, two piece cockade. Size 53 and dated "I" (1982).
NVA marked Air Force Officer Winter hat or "shapka". Imitation fur, two piece cockade. Size 55 and dated "R" (1976).
Female parade cap. Two piece cockade. Size  53, no date, no markings.
Female cap, gabardine fabric, two piece cockade, silver piping. Size 52 and dated "O" (1974).