The cross-section of a mattress made of <a href="https://en.wikipedia.org/wiki/Coconut" class="extiw" title="en:Coconut">coconut fibres</a>(middle; brown line), a spcial <a href="https://en.wikipedia.org/wiki/Foam" class="extiw" title="en:Foam">foam</a> (above and below the coconut fibres; withe lines) and a mixture of <a href="https://en.wikipedia.org/wiki/Hemp" class="extiw" title="en:Hemp">hemp</a>- and <a href="https://en.wikipedia.org/wiki/Domestic_sheep" class="extiw" title="en:Domestic sheep">sheepwool</a> (above and below the foam; grey-brown ring)
<a href="//commons.wikimedia.org/wiki/User:D-Kuru" title="User:D-Kuru">D-Kuru</a>
CC BY-SA 3.0 at
<span class="int-own-work" lang="en">Own work</span>