What this instrument is used for?

Question

Just like everyday, I was at the climbing wall this morning, when I reached, there was a group (I have not seen anyone of them there, ever, it being a local place, I know almost everyone who comes there in my time slot) who had finished their practice and were winding up their stuff. I saw an instrument that I have never seen, or seen anyone using it. After spending a couple of hours searching for it, I could get a picture of what it looked like.

• What this instruments is?
• I very well know that I should not try to use an instrument that I don't know about right away on a climb, instead I should get it, learn how it should be used in proper way and then try it over a climb (preferably under an experience observer).

Answer 1

It's a self-belay device for rappelling that works just like a simple figure-eight, but there is a configuration where the lever on the left allows you to release yourself under load. It's meant for canyoning, so you can rappel down some distance before taking a plunge into a pool that's a bit further down than your are comfortable with jumping directly.

Here's a video (bad quality unfortunately) that shows how it works: https://www.youtube.com/watch?v=tvCYLkG-xec

Answer 2

It is a self-locking descender with other uses as well. The official page by the manufacturer states that it's not only meant to be used on canyoning:

Multiuse descender device, the only one in the world which can be opened under load. Multi-purpose device suitable for canyoning, special forces, rescue and military application. As a descender it fits ropes from 5 to 13 mm in diameter. Useful for many other actions as lifting, belaying, rescue etc. It works with ropes between 9 and 12 mm

Unfortunately it looks like the manual isn't available online.

This is a page with some more comments about the device.