Recording device in jet pack (5,3)
I believe the answer is:
black box
'recording device' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'jet pack' is the wordplay.
'jet' becomes 'black' (similar in meaning).
'pack' becomes 'box' (I can't explain this - if you can you should give a lot more credence to this answer).
'black'+'box'='BLACK BOX'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for black box that I've seen before include "Flight data recorder" , "Electronic device in aircraft recording flight information" , "Aircraft's flight recorder" , "item revealing how Jumbo killed people?" , "Plane's flight recorder" .)