What is this prototype?

[BrainPortable]

Nowadays,I found that someone is selling this kind of TI-Nspire Prototype online.I have checked out the Tiplanet prototype gallery,but no any prototype picture looks exactly like this one.
This calculator looks both like Phoenix and Nspire CAS+,however,there is something different,for it's letter keys are in the color of green,and it has a independent [approx] key on the right-bottom of the keyboard,and it got no name.

[critor]

It looks like a TI-Nspire CAS+ P1-DVT1 :
gallery/album.php?album_id=147

The one we've been lent by Datmath came with :
- OS 1.0.494 from July 27th 2006
- Boot1+Boot2 1.0.491 from July 26th 2006

So it's between the TI-Phoenix P1-EVT and the TI-Nspire CAS+ P1-PVT tested in schools in 2006-2007.

The preinstalled OS 1.0.494 has been dumped : archives_voir.php?id=4599
The prototype can be updated to the more recent OS 1.0.526 from August 11th 2006 using the TI-Nspire Computer Link 1.0 : archives_voir.php?id=4600

Updating to most recent 1.0.529/554 versions won't be possible without reflashing both Boot2 and Boot1, as the preloaded versions are using the development keys where the most recent OSes switched to the production keys.
Boot2 reflashing can still be performed via an USB/TTL interface.
But Boot1 reflashing won't be possible for now, because :
- we have no Ndless+ version running on OS 1.0.494/529
- and we have no working Ndless+ Boot1 flashing program

[BrainPortable]

Thank you for your answering.
Besides,it seems that I didn't look through the gallery careful enough...