Abstract: A seat or back for a chair comprises a frame having a first edge strut and a second edge strut, the first and second edge struts being on opposite edges of the seat or back. The first edge strut has a groove along all or most of its length, an elongate insert, and a mesh, the mesh being attached to the insert along an edge of the mesh. The insert has a section shaped to correspond to the section of the groove, such that the insert can be urged into the groove, the compression of the groove holding the insert in place.