Hat security features catch (9)
I believe the answer is:
chinstrap
'hat security' is the definition.
'chinstrap' can be an answer for 'hat' (I've seen this before). I'm not sure about the 'security' bit.
'features catch' is the wordplay.
'features' becomes 'chins' (chin is a kind of feature).
'catch' becomes 'trap' (trapping is a kind of catching).
'chins'+'trap'='CHINSTRAP'
Can you help me to learn more?
(Other definitions for chinstrap that I've seen before include "hat" , "This secures cover for head" , "Band" , "Bit of helmet" , "fastener" .)