An insert adapted to be inserted between a foundation of a bed and a mattress of the bed. The insert includes a frame having a first side rail and a second side rail spaced apart from the first side rail. A plurality of elongate upper slats extend between the first side rail and the second side rail of the frame at a first level with respect to the frame and are spaced apart from one another. A plurality of elongate lower slats extend between the first side rail and the second side rail of the frame at a second level located below the first level of the upper slats. Each lower slat is located below a gap formed between a pair of adjacent upper slats. A mounting member resiliently supports the ends of two adjacent upper slats and rigidly supports the end of a lower slat that is located below the gap formed between the two adjacent upper slats, whereby the firmness of a mattress overlying the insert can be selectively adjusted.

A bed frame having flexible slats which are adjustable in a horizontal plane and having at least one bearing element for supporting one end of at least one flexible slat on a longitudinal beam of the bed frame is provided. The bearing element is movable over an arbitrary displacement path along the longitudinal beam. The bearing element includes a housing which accommodates the respective end of the flexible slat and in which at least one spring-loaded detent device, which is actuatable by hand, is situated and which engages with associated receiving profiles in the longitudinal direction of the longitudinal beam and is lockable at that location.

An insert adapted to be inserted between a foundation of a bed and a mattress of the bed. The insert includes a frame having a first side rail and a second side rail spaced apart from the first side rail. A plurality of elongate upper slats extend between the first side rail and the second side rail of the frame at a first level with respect to the frame and are spaced apart from one another. A plurality of elongate lower slats extend between the first side rail and the second side rail of the frame at a second level located below the first level of the upper slats. Each lower slat is located below a gap formed between a pair of adjacent upper slats. A mounting member resiliently supports the ends of two adjacent upper slats and rigidly supports the end of a lower slat that is located below the gap formed between the two adjacent upper slats, whereby the firmness of a mattress overlying the insert can be selectively adjusted.