This model is of the early E/F versions of the Dornier Do 17 medium bomber that was used by the Condor Legion in the Spanish Civil War, unlike the later radial powered models these aircraft were powered by relatively low power BMW V12 engines. Experience in the SCW revealed that the Do 17E/F were underpowered and underarmed but despite this a few of these aircraft were still used in secondary roles in WW2.
The spherical depresssion underneath the model is for mounting it on a 4.5mm BB.