Looking down the business end of a German Pak 40 75mm AT Gun. Used from 1943 onwards en mass it would kill any Allied tank and was only bettered by the British 17 pdr and the German '88. Like the the latter weapons, the Pak 40 was at the limit of what was usable as a towed gun.
I used a Russian head on the gun aimer so he becomes a German who has looted a warm Russian fur hat.
This is a metal 28ml model from Warlord Games, part of their excellent Bolt Action range.
A pic using fill in flash: more detailed but less evocative.