DZO - Dolnośląskich Zakłady Odlewniczych - Foundries of Lower Silesia A factory established in 1828 in the city of Iława, east of Szprotawa. The factory started as a foundry, but later also started producing agricultural tools, instruments for the mining industry. The factory was the largest in Szprotawa and employed more than 1,000 workers in 1960. The factory was closed in the 1990s.