Features: _x000D_ 1. Chrome-plated surface, beautiful and corrosion resistance. _x000D_ 2. Made of aluminum alloy, stronger bearing capacity. _x000D_ 3. High hardness, low noise and rustproof. _x000D_ 4. Prevent dust from entering to extend the service life. _x000D_ 5. Precision roller, no need to lubricate. _x000D_ 6. Fit for silent, high-speed and precise equipment. _x000D_ _x000D_ _x000D_ Specifications: _x000D_ Model: SBR16UU _x000D_ Material: Aluminum alloy _x000D_ Quantity: 4pcs _x000D_ Shaft Diameter: 16mm/0.63in _x000D_ Size(L*W*H): 4.5*4.5*3.3cm/1.77*1.77*1.30in _x000D_ Weight: Approx. 573g _x000D_ _x000D_ Package Includes: _x000D_ 4 x Open Linear Bearing Slide _x000D_ _x000D_ _x000D_ Note: _x000D_ Please allow 1-3mm error due to the manual measurement. Thanks for your understanding. 1Chrome-plated surface, beautiful and corrosion resistance. 2Made of aluminum alloy, stronger bearing capacity. 3High hardness, low noise and rustproof. 4Prevent dust from entering to extend the service life. 5Precision roller, no need to lubricate.