【High-quality material and long service life】 Made of high-quality zinc alloy, corrosion-resistant and not easy to rust. Long service life. The brushed surface is smooth and can be used indoors and outdoors. The ball is tightly connected to the bearing and acts as a buffer door. 【270-degree rotation angle, smooth opening and closing】 Built-in single ball bearing, the ball and the bearing are firmly connected, the distance between the bearing and the blade is small, the ball shaft design, coupled with the 270-degree rotation Angle, effectively ensures the flexible and smooth opening effect and reduces the noise when opening. 【Reduce noise, smooth operation】 The stainless steel hinge is equipped with scientific positioning holes and solid shafts, which can balance the weight, reduce noise and operate smoothly. It can be easily installed on the edge of the door. 【Easy to use】First use the tool to mark the mounting holes on the door frame, compare the positions when installing the hinges,