These U-shaped channel rollers are made of stainless steel, nylon, and acetal polymers that are robust, versatile, wear-resistant, and ensure long-term reliability without failure These U-shaped channel rollers are suitable for multiple applications such as movable room dividers and window mechanisms and adapts to environments such as residential and commercial spaces for quiet operation The dimensions shown in the picture ensure proper compatibility with a variety of windows and divider tracks These U-shaped channel bearing rollers feature reinforced and coated abrasion-resistant materials for superior safety and consistent stability against oxidation. Ideal for window mechanisms and movable dividers allowing smooth operation with reduced resistance These U-shaped channel rollers are designed for quick installation and require drilling and complicated tools. Simply place it on your truck and secure it in place, Manufacturer: LEMEIGUO