Whatever it is, feels pretty much just like 100% down (I'm no princess-and-the-pea-type). It does come compressed, but I tossed it in the dryer for a bit with some dryer balls and it fluffed right up. I do sort of feel like the edges are still a little flat, but I'm giving it time to puff and like it anyways. Warm on cold nights, not too warm (yet) on warmer nights. 

Pros: Great value, cozy 
Cons: Some uneven fluffiness, comes super flat packed and needs TLC