HIGH QUALITY: It is made of high quality zinc alloy and is extremely durable. All curtain rollers can roll and glide smoothly in the rail. Lightweight but sturdy, easy glide gliders. Perfect size: this rail roller metal sizes: total width: 18 mm; total length: 14 mm; pitch: 9 mm. Versatile, perfect for curtains, sheers, jugs, shower curtains. APPROX DESIGN: The hook is designed to be hung on a 360 degree swivel rail suspension, which is fashionable and classic. The silent wheels are covered with rubber that glides smoothly and quietly and creates a quiet and elegant living environment for you EASY AND CONVENIENT - For pleated curtains with needle hooks, simply insert the needle hooks into the grommet at the bottom of the carrier. For curtains with eyelets or loops on the back, simply add the hooks. Scope: Ideal for attaching curtain panels, room dividers, curtains, curtains and valances. Widely used in windows, closets, bedrooms, offices, restaurants, sliding doors, etc.