In addition to its practical benefits, the aluminum alloy door and window pulley also offers a sleek and modern appearance. Its good finish and streamlined design make it an attractive addition to any sliding door or window system. This pulley not only enhances the functionality of your doors and windows but also adds of elegance to your space. Features -Color:Silver -Material:Aluminum Alloy -Size:8.20X4.00X1.60cm/3.22X1.57X0.63in -Screw hole center spacing:17mm -Wheel outer diameter:28.5mm -Wheel inner diameter:23.5mm -Sturdy material: constructed from sturdy aluminum alloy, the sliding door pulley is designed to withstand heavy use and provide long-lasting reliability -Smooth and quiet: the bearing and double wheels design ensure smooth and quiet operation, making it ideal for residential and commercial use -Wide compatibility: good for use with sliding doors, windows, and patio doors, this pulley is a versatile and practical addition to your hardware collection -Long-lasting performance: the sturdy materials and construction ensure long-lasting performance, reducing the need for frequent replacements -Easy to install: designed for easy and secure installation, this sliding door pulley can be quickly and securely fitted to your existing doors and windows Package list: 4 Pulleys