Fox RP23 Boostvalve Pro-Pedal Rear Shock 165/38mm, never used.
Shock was taken off a new frame and replaced with a different make, so has just been stored since then.
Hopefully the photos should show all info needed, but just to clarify - on the side of the shock, it lists:-
Boost Valve Tune 225
Rebound Tune M
Velocity Tune L
If you have any questions - please ask.