These are 4 mid century modern Knoll arm chairs designed by Richard Schultz. The have metal bases and upholstered turquoise canvas backs and seats. One of the chairs is a little lighter turquoise blue than the other three. Dimension: seat width: 19.25″, seat depth: 16″, seat height: 17.5″, back height: 31.5″.
1 set of 4 Knoll chairs are available: $400 for all 4