Hi Igor, Exped don't mention the breathability in their spec unfortunately - in all honesty I think you can assume the breathability will be pretty low considering that the bivvy bag is 100% Nylon with a PU- coating.
That said it's an ultralight bag so the idea is that it's more for 'surprise' use than planned outings - or you accept the lower breathability for your lightweight endeavours ;)
Hi Igor, Exped don't mention the breathability in their spec unfortunately - in all honesty I think you can assume the breathability will be pretty low considering that the bivvy bag is 100% Nylon with a PU- coating.
That said it's an ultralight bag so the idea is that it's more for 'surprise' use than planned outings - or you accept the lower breathability for your lightweight endeavours ;)
I hope this helps! Best regards.