Magnifying glass? Ring for delivery (5)
I believe the answer is:
loupe
'magnifying glass?' is the definition.
(I've seen this in another clue)
'ring for delivery' is the wordplay.
I cannot quite see how this works, but
'ring' could be 'o' (letter resembling a ring) and 'o' is found within the answer.
The remaining letters 'lupe' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for loupe that I've seen before include "Jeweller's eyepiece" , "Jeweller's magnifying glass" , "instrument in view of fine work" , "Jeweller's eyeglass" .)