There are two variations of this kit doing the rounds. Most of it is the SF Tantalus system (improved and turned into PECOC), while the rest of it is some of the PECOC concept demonstrators kit that is flying around. Nothing I am aware of is on regular issue. 'Normal' people wearing it may be attached troops.
The its designed to allow water out, the feedback from most troops is they don't like it lets small items fall through the gaps; therefore currently discounted from PECOC.