The middle door pulley bracket is made of metal, which is stable and durable; the roller part is made of high-strength engineering plastic, which has good wear resistance and stability. Function: Through precise engineering, the sliding door rollers feature a unique design that reduces friction for a smoother experience; Structure: Constructed from metal materials, they offer a sharper, richer visual experience and stable performance; Installation: This automotive roller assembly is designed for easy installation, quickly solving your sliding door problems; It helps to alleviate the jamming, abnormal noise or shaking of the sliding door during use and improve the operation of the door body., Manufacturer: PENGNAQP