Inflexible equipment I had (5)
I believe the answer is:
rigid
'inflexible' is the definition.
(I know that inflexible can be written as rigid)
'equipment i had' is the wordplay.
'equipment' becomes 'rig' (rig is a kind of equipment).
'i had' becomes 'i'd' (contraction).
'rig'+'id'='RIGID'
(Other definitions for rigid that I've seen before include "Unable to bend" , "completely" , "Stiff and inflexible" , "Not flexible" , "Incapable of or resistant to bending" .)