Probably a rebuilt U 4, some sources mention this a Udet U 3. Photos from an air race in Argentine
Type Two seated sportplane  (Only a project according to Lange), development from U-2 
Engine 1 Siemens Sh 4
Dimensions Length  , height  ,  span  , wing area   ,
Weights Empty , loaded  , max. take off weight  
Performance Max.. speed  , cruising speed  , range , endurance  , service ceiling   , climb