Our factory-produced {China High Speed 5x21x7 625ZZ u groove guide pulley sealed rail ball bearing} is a high-quality product that is essential in various industrial applications. Made with precision and accuracy, these bearings have a 5x21x7mm dimension and feature a u groove guide pulley and sealed rail ball design. They can operate at high speeds and withstand heavy loads, making them suitable for use in machinery, conveyors, and robotics. We guarantee that our bearings are of superior quality and will last longer than alternatives on the market. As a factory, we take pride in our work and strive to provide our customers with the best products and services.