A Yellow Keer by Dutch designer Reinier de Jong who is based in Rotterdam.
It can be used in 4 different ways: as a stool, side chair, lounge chair or as a bench.
Each lightweight polyethylene element is 20cm (8″) wide and can be connected to another by built-in magnets. Hence the width of KEER can be adjusted to the use: Two elements are recommended for use as a stool or a side chair and three elements are optimal for a lounge chair. By conecting more elements one creates a sofa.