Equestrian controls (5)
I believe the answer is:
reins
'equestrian controls' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for reins that I've seen before include "Harnesses" , "Straps to control" , "They're used to control" , "Bridle straps" , "Guiding straps" .)