1: Casters: ordinary casters, pu wheel (soft material, suitable for wood floors, and the engine room). 2: Legs: the thickness of the metal framework of a direct impact on the life of the chair. Surface treatment: paint, paint (surface gloss, easy stripping), plating (not wooden plating), Electroplating good quality, it is not easy to rust. 3: gas bar called stretch down lever for adjusting the height and rotation of the chair. 4: hold the seat part of the chassis, and the following is connected to gas bar. 5: Seat made of wood, sponge, fabric composition. Wood quality consumers generally feel. Sponge: regenerated cotton, new cotton. 99% of manufacturers are both with the use of thicker and hard, the higher the cost, the appropriate thickness, hardness can be appropriate. Hand pressure seat, Fabric: Ma Rong, mesh, leather. Pressure plastic box Internet cloth. Such a chair, more in line with breathability. 6: handrail thickness affect the quality. 7: The back seat is connected (Corner) and the seat back is split, the use of steel or steel connection plates, usually 6mm or 8mm thick. But smaller than the width of 6cm steel, must 8mm thick. 8: back steel frame, plastic frame of the chair, using a combination of mesh made of a breathable. 9: lumbar pillow reflect the comfort of the chair. 10: headrest performance comfort of the chair.