Twisting spoils piece of equipment (4)
I believe the answer is:
tool
'piece of equipment' is the definition.
'tool' can be an answer for 'equipment' (a tool is a piece of equipment). I am not certain of the 'piece of' bit.
'twisting spoils' is the wordplay.
'twisting' says the letters should be written backwards (letters twist back).
'spoils' becomes 'loot' (both can mean a reward or proceeds).
'loot' in reverse letter order is 'TOOL'.
Can you help me to learn more?
(Other definitions for tool that I've seen before include "Cat's-paw; impress design on" , "one of 12 [SPADES] , for example" , "Appliance" , "Person exploited" , "Instrument, implement" .)