Material: These white curtain hooks are made of sturdy plastic and stainless steel, which have good load-bearing capacity and are not easy to break, allowing them to maintain durability for a long time. Easy to Install: Our curtain track sliding pulley is simple in design and quick to install. No complicated skills or tools are required. Just align the center column of the pulley with the curtain slide rail and snap the pulley in. Wide Application: Plastic ceiling rollers can be used for window, shower curtains, and door curtains in various places such as offices, restaurants, hotels, etc. Size Adaptability: The curtain track rollers are designed for most standard curtain tracks and rails, making them a universal solution for window treatments. Please check the size of the curtain rod before purchasing. Material: PVC Plastic and Stainless Steel Total Size: 28 x 16.2 mm/ 1.1 x 0.64 inch (L*W) Wheel Diameter: 14.4 mm/ 0.57 inch Center Column Size:5.6 mm/ 0.2 inch Thickness: 4mm/0.16 inch Colour: White Package Includes: 30pcs x Curtain Track Glider Pulley