Semi impregnated chainEnvironmental protection dip, smooth without burr, no hand injury, prevent rust, better load-bearing, children play more assured.Two connection modesS hook is pressed to prevent falling off and firmly fixed. Quick link buckle, detachable, easy to install.Prevent back somersaultThe principle of ergonomics design is wrapping design, which forms an encirclement. Prevent the baby before and after. Swing left and right. Complies with CPSIA.