The pocket spring mattress is made by springs covered with nonwoven fabric. The springs are sewed in line from head to toe and joined rows around a central point. They work as independent dampers. This technology give rise to a very independent beds.
Different technologies pocket springs as the number of springs per m2 they possess. The mattresses can have from 500 springs until about 1300 spring in one 150x190 mattress. As you can see in the photo in a higher number of springs, larger bearing surface.
In the top of the pocket spring are often added as latex and memory foam technology to increase the comfort of this product.