What's packed inside the cushion?
General sponge on the line, and other so-called health cassia, buckwheat, it is not necessary, a cushion is expected to use for six months, so there is no need to buy too good.
The market now uses EVA (similar to sports shoes soles of the foam layer), EPE (pearl cotton), and even with recycled materials (black heart cotton) as a filler, this should be carefully identified.
