The one with Besonders Armschoned and no 600 is from 1988 to early 1989 before 600 was put on the racquets. It has the same markings as the Elite Pro and Elektra Pro from 1988.
Also the original Cap System Grommets did not have the part number on them. FYI the OG CAP Systems are TK10.
Djokovic Racquets specs: weight-358g balance-32cm SW-370 Flex 60RA