A slatted base is what the word says: a base made of slats. This support can work in different ways. Either pumps are used on the sides of the slats, or the slats are flexible. It is important to always have either pumps or curved slats. Thick hard slats that are simply mounted in a bed frame offer no back benefits.

Slatted bed bases can have different sizes. Often two slatted bases are put together if it is a bed for two people. In that case, a spacer is used.

Slatted bases can either be set on legs or laid in bed frames.

Advantages:

Different ergonomic zones.
The space between the slats allows the mattress to breathe.
Some slatted bases are adjustable in hardness.
Putting them on legs can make them very firm.
Exist in both fixed, manually and electrically adjustable models. The adjustability on a slatted base is higher than on a box spring. This allows, for example, to read a book while sitting upright in bed. Just make sure the mattress is flexible enough if you want to do this. In general, slatted bases are slightly harder than box springs.
Ability to work with different "frames" inside the slatted base. Models such as the Lattoflex Hybrid 1, Beka Balancer III plus, Beka Sensitec III plus, ... Have 3 frames. The first frame is fixed and provides stability. The second frame is manually adjustable and can be used to click the slatted base together. This is good for persons whose blood circulation in the legs is less smooth. Remember, it is unhealthy for the legs to be higher than the head. The third frame is electric. This frame allows the head and foot ends of the slatted base to be raised.
Can be used for almost any type of mattress.

Disadvantages:

Decoratively less attractive unless placed in a bed frame.
When using a center piece to connect the two slatted bases, it is more difficult to clean under the bed. In this case, the bed should no longer be moved.
Slatted bases with pumps on the sides may begin to make noise over time.