Features 1、Chrome-plated surface, beautiful and corrosion resistance. 2、Made of aluminum alloy, stronger bearing capacity. 3、High hardness, low noise and rustproof. 4、Prevent dust from entering to extend the service life. 5、Precision roller, no need to lubricate. Specification Features: 1. Chrome-plated surface, beautiful and corrosion resistance. 2. Made of aluminum alloy, stronger bearing capacity. 3. High hardness, low noise and rustproof. 4. Prevent dust from entering to extend the service life. 5. Precision roller, no need to lubricate. 6. Fit for silent, high-speed and precise equipment. Specifications: Model: SBR16UU Material: Aluminum alloy Quantity: 4pcs Shaft Diameter: 16mm/0.63in Size(L*W*H): 4.5*4.5*3.3cm/1.77*1.77*1.30in Weight: Approx. 573g Package Includes: 4 x Open Linear Bearing Slide Note: Please allow 1-3mm error due to the manual measurement. Thanks for your understanding. Package List