top looks like a filter cap,the other maybe radio part.
Thanks for your answer. Is there a reference list in which the number is mentioned?
Or a photo or plan in which the cap is shown?
The 5c tells which system this is from on an A/C, I have a list somewhere but I cannot find it, As I remember 10 is the systems number for radio items.
just google as simple: WW2 RAF AIR MINISTRY HEAVY DUTY TERMINAL BOX