Hi Smytrous,
Their Ultimate collection uses blended Talalay latex which is a blend of 30% natural and 70% synthetic rubber. They are 100% latex from top to bottom and don’t contain any polyfoam. The specs of the Ultimate line are in post #2 here. You can see the specifics of their cover here and their fire barrier here.
The “organic” line uses an organic cotton cover quilted with organic wool (which is also used as the fire barrier) and uses 100% natural Talalay (not organic) instead of blended Talalay and is also 100% latex from top to bottom with no polyfoam. There isn’t any Talalay latex that has an organic certification.
There is more about 100% natural vs blended Talalay in post #2 here.
Phoenix