Simply question , how to use it? what advantages?
Which material are you talking about? Looks like they have a couple of different products with Diadrain as a name. One looks similar to Enkafusion and the other looks like Enka with a resin blocking membrane covering it (similar to the MTI hose cover).
The Enka product is used for resin distribution so I would assume that one is used for that and the one with the resin blocker would be used for vacuum. Just guessing.
I can only find roof materials.
Riff,
I hit the web and found this (see page 2 and 4): http://www.diatex.com/IMG/pdf/infusion_accessories_indice_g.pdf
The membrane line is a flat evacuation hose and copy of the MTI hose. They made it for use on the part to infuse from the outside to inside.
Yes correct its Diatex stuff , still dont know how to use it , and what exactly expect 
Which one, the membrane vent thing? it’s just a flat mesh that is covered in resin-impermeable membrane. Vapors, gasses, etc can go through it, but resin will not. That way, when you let resin into the infusion, it will not suck out.