This was originally intended for a military ambulance medical technician, or raised gunner position. 

This is a fairly standard adjustable 5 point harness, with the rotating Schroth centre buckle.  The anti-submarining attachment at the bottom remains attached, and the waist and shoulder straps release from the centre buckle..  

However, what makes it unusual are the vehicle attachments, which are designed to offer you more flexibility than a normal harness.  

At the shoulders, it is has quick release buckles that allow you to attach removable inertia reel straps.  Once attached, it behaves like a normal car seat belt, allowing you to sit forwards, but locking it you move too quickly.   The reels also have a manual locking lever, so they can be fixed in place.  

There is a choice of two sets of these.  One 1.9m extended / 0.17m retracted, and the other 2.2m extended / 0.47m retracted.

At the waist it has two longer drum reels, which are removable from the harness, but not quick release.  Also inertial locking, and manual locking.  

The idea of the system is that you can sit normally in a seat, attached at 4 points rigidly in place.  You can release the locks on the shoulder straps to move your upper body around a short distance (ie, tending a patient directly in front of you), or you can release the shoulder straps completely and unlock your waist, allowing you to move further into the cabin, while still restrained back to the vehicle (top cover on the 50 cal, blatting bad-guys).

This was bought for evaluation purposes on a military vehicle many years ago.  It's never been used in anger, and has only been fitted up to a mock up vehicle.  It's about 20 years old, so some of the fixings have a little cosmetic rust.  The large waist drums have the words 'design sample' engraved upon them.  The harness itself is in pretty good condition with no frays or damage.  It may be a design sample, but is fully manufactured to standard schroth practices (it'll work, it's not just representative).  

It is obviously not homologated, e-marked or approved, and carries no ratings of any kind.  It will not be road legal, so I would suggest is useful for an off-road military or agricultural vehicle, carnival float, or static installation only.  Whatever you choose to do with it, please make sure it is fit and safe for that purpose. 

I can assure you that you're highly unlikely ever to see another one!

Collection from Cambridge, or postage via simple delivery.