The flip side perhaps of men leaving salt mine (5)
I believe the answer is:
tails
'the flip side' is the definition.
(I've seen this in another clue)
'of men leaving salt mine' is the wordplay.
'of' indicates an anagram (the answer comes from or 'of' the letters).
'leaving' suggests deleting specific letters.
'salt'+'mine'='saltmine'
'saltmine' with 'men' taken away is 'salti'.
'salti' anagrammed gives 'TAILS'.
'perhaps' acts as a link.
(Other definitions for tails that I've seen before include "Gambler's choice" , "Ends" , "Animals' extremities" , "Morning coat" , "as opposed to heads" .)