Set of 4 mid-century vintage industrial dining chairs by Wim Rietveld for Kembo, Netherlands 1950s

Set of 4 industrial design chairs designed by Wim Rietveld for Kembo, 1950s. The heavy chairs have a slim anthracite steel frame with light wooden armrests and black skai leather upholstery. Good vintage condition. Light signs of use on the frame. The leatherette seats have been reupholstered over time and have a slightly more matt appearance than the backrests.