Sprung Slats. . . .

Slats are the most common type of mattress support system used on bedsteads, and sprung slats a natural development of this design.

A base with sprung slats features curved wooden slats, usually made of beech, which sit within the frame. The natural bounce of these gently curved slats means they will adjust to your profile where you exert the most pressure. The bottom image shows the sprung slat with pressure applied and without pressure being applied.

A bed larger than a single size will often have two rows of slats (as in the image below), each row is joined at either end. The join may be a screw, but is usually a plastic socket which the slat is slotted into (to allow flex and movement).

Sprung slatted bases tend to soften the feel of a mattress, so a traditional (non-sprung) slatted base will be the preferred option for those who like a firmer feel.

The image below shows a typical slatted bed base. The slats are curved upwards and flex as weight is applied.