打吊钳姿势要正确 Da diaoqian zishi yao zhengque Designer Sichuan Petroleum Administration Bureau of Drilling (四川石油管理总局钻探局) Date early 1950s Publisher First Printing Factory of the Northwest Military Region (西北軍區第一印刷廠) Size 54x78 cm. Call nr. BG E37/285 Collection Landsberger collection