Lash components the wrong way round (5)
I believe the answer is:
strap
'lash' is the definition.
('strap' can be a synonym of 'lash')
'components the wrong way round' is the wordplay.
'components' becomes 'parts' (I've seen this before).
'the wrong way round' is a reversal indicator.
'parts' in reverse letter order is 'STRAP'.
(Other definitions for strap that I've seen before include "Narrow strip of leather" , "Leather fastener" , "Restraining fastener" , "Leather thong" , "Secure" .)