In the lower part of the face is a series of rings (5)
I believe the answer is:
chain
'series of rings' is the definition.
'chain' can be an answer for 'series' (chain is a kind of series). I'm not certain of the 'of rings' bit.
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for chain that I've seen before include "Connected sequence" , "Links - sequence - 22 yards" , "lots of shops?" , "Line of links" , "Coupling" .)