Croatia, 1991, local patriotic anti-war issue "Zagreb", complete of 12 "proof" stamps. The sheets of this stamps were used for the preparation and tuning of the printing machine when overprinting the Zagreb issue. The 60 din stamp was inserted into the machine in reverse because of the above inscription of the name of the former state of Yugoslavia. 

The quantities of these trial stamps are from 5 to 50 sheets of each value. The rarest is 70 dinar. Values of 10, 30, 60 and 300 dinar are found in several sheets, and there are more sheets from 500 and 700 dinar denomination

The stamps are mint, never hinged and in excellent condition

Winning buyer pay US$3.00 packing and shipping, US$6.50 registered