He lets charm sort out hard hat (5,6)
I believe the answer is:
crash helmet
'hard hat' is the definition.
(thesaurus)
'he lets charm sort' is the wordplay.
'sort' indicates an anagram.
'he'+'lets'+'charm'='heletscharm'
'heletscharm' is an anagram of 'CRASH-HELMET'.
'out' acts as a link.
(Other definitions for crash helmet that I've seen before include "Motorcyclist's headgear" , "Motorcyclist's head protector" , "Protection for head" , "Skid lid" , "Garb for bikers" .)