Inner foam specifications:
The best way to know is to check the package for the density of the foam.
Cheap foam density normally is 10-15kg/m3. density, mid-grade foam is 18-22kg/m3.
High density and good foam is over 25kg/m3. density.
Usually, 27kg/m3 foam is considered the ideal density to properly support the human body and compressed roll up packaging.
The lighter grade foam won't support you and will quit returning to its original shape after only a few months.or can not EXPAND PR