I-phone copy of a photo from a personal photoalbum of an unknown German pilot. IMHO it represents a Do-217M with fully glazed nose and powered by DB-603 engines. Does the sign represent 1000 operations or flight hours? The photoalbum is owned by the Poldermuseum in Waverveen (NL)

IWM say this is a prototype of the Do 217J-1, a heavy but nevertheless effective night fighter. The airframe served with 4./NJG 3 as 3C-MT and was then supplied to the Italian air force which received twelve Do 217Js to equip one squadron of 60° Gruppo. The unit did poorly and this one was apparently lost in August 1943. Photo from: Imperial War Museums

The Dornier Do 217E-1 entered service in late 1940. A development of the Do 17, the Do 217 was classed as a heavy bomber by the Luftwaffe. This new aircraft carries its factory callsign TC-ZK. Photo from: Nederlands Instituut voor Militaire Historie