The «Luxury (180 x 200 cm, Natural Core)» and the «Coco Futon» from Karup Design have several key differences:

## Dimensions
- The «Luxury» futon is 180 cm wide and 200 cm long, while the «Coco Futon» is 80 cm wide and 200 cm long.

## Height and Thickness
- The «Luxury» futon is 16 cm thick, whereas the «Coco Futon» is also 16 cm thick but has a different internal structure.

## Mattress Fill Material
- The «Luxury» futon has a natural core, but the specific materials are not detailed in the provided data. In contrast, the «Coco Futon» has a core of coco fibre plate mixed with cotton and 5-10% polyester.

## Sleeping Comfort
- The «Luxury» futon is described as having a hardness grade of 3, which is hard, while the «Coco Futon» provides medium-soft sleeping comfort.

## Compatibility and Use
- The «Luxury» futon is suitable for back, side, and stomach sleepers, whereas the suitability of the «Coco Futon» for different sleeping positions is not explicitly stated, though it is generally adaptable to body shape.

## Note on SKU
- The SKU numbers mentioned are different: «762917180200» for the «Luxury» futon and «762901080200» for the «Coco Futon», indicating they are distinct products despite any confusion.