A chair with mutually synchronous deflection between the backrest and seat over a range between a zero position of back inclination (R o) and seat inclination (S o), respectively, and a maximum back inclination (R max) and seat inclination (S max), respectively, comprising: a) an underframe designed to be placed on the floor; b) a mechanism with a spring unit arranged therein, which mechanism effects the synchronous deflection; c) a carrier unit with a base support that is rigidly attached to the underframe and through which a fixed first axis of rotation and a fixed second axis of rotation extend; d) a back support that is articulated on the first axis of rotation and through which a third axis of rotation extends, which third axis moves about the first axis of rotation when the mechanism is adjusted; e) a base plate that rests movably on the base support at the front and is articulated on the third axis of rotation at the rear, wherein f) the base support is U-shaped and has a center part and two upwardly extending arms, each of which having an upwardly projecting fitting that engages in a respective associated opening in the base plate and, when the mechanism deflects, a relative movement between the fixed fittings and the openings occurs; and g) the two openings are aligned in the direction of the seat depth and thus at a right angle to the transverse axes of rotation (D1, D2, D3), characterized in that h) a roller is arranged on the second axis of rotation on the outside of each of the two arms of the base support for the purpose of reducing friction, on which roller the base plate rolls during the synchronous deflection of the backrest and seat; i) the rollers are embedded in roller tracks that are recessed on the underside of the base plate in the form of grooves, whereby a guide is created between the rollers and the base plate; and j) pockets positioned on the base plate in the vicinity of the openings are provided which serve the function of receiving cover strips that close off the openings from the underside of the base plate as protection against pinching. a) an underframe designed to be placed on the floor; b) a mechanism with a spring unit arranged therein, which mechanism effects the synchronous deflection; c) a carrier unit with a base support that is rigidly attached to the underframe and through which a fixed first axis of rotation and a fixed second axis of rotation extend; d) a back support that is articulated on the first axis of rotation and through which a third axis of rotation extends, which third axis moves about the first axis of rotation when the mechanism is adjusted; e) a base plate that rests movably on the base support at the front and is articulated on the third axis of rotation at the rear, wherein f) the base support is U-shaped and has a center part and two upwardly extending arms, each of which having an upwardly projecting fitting that engages in a respective associated opening in the base plate and, when the mechanism deflects, a relative movement between the fixed fittings and the openings occurs; and g) the two openings are aligned in the direction of the seat depth and thus at a right angle to the transverse axes of rotation (D1, D2, D3), characterized in that h) a roller is arranged on the second axis of rotation on the outside of each of the two arms of the base support for the purpose of reducing friction, on which roller the base plate rolls during the synchronous deflection of the backrest and seat; i) the rollers are embedded in roller tracks that are recessed on the underside of the base plate in the form of grooves, whereby a guide is created between the rollers and the base plate; and j) pockets positioned on the base plate in the vicinity of the openings are provided which serve the function of receiving cover strips that close off the openings from the underside of the base plate as protection against pinching.