This SBR Linear Guide Rail Set features SBR20-1200 mm linear motion guide rails, including 2 x 47.2 in/1200 mm length SBR20 guide rails and 4 x SBR20UU slide blocks. It offers a dynamic load per block of 882 N and a static load per block of 1370 N. Constructed from carbon steel and aluminum with a chrome-plated surface for rust resistance and high durability, it ensures long-lasting use. The set includes 4 built-in aluminum slide blocks and ball bearings for smooth, unobstructed sliding. Experience low noise sliding due to the perfect pairing of aluminum SBR slide blocks and carbon steel linear shafts, with built-in ball bearings providing low friction movement that is smooth and stable, allowing for more labor-saving control. Achieve high precision with precise circular shaft dimensions and straightness, ensuring high accuracy, repeatability, and stability in motion. The sturdy aluminum base and slide block feature accurate mounting holes for reliable installation and connection. This versatile SBR linear rail set is suitable for all kinds of high-load automation equipment and DIY projects, such as router/mill/lathe sleds, 3D printers, laser engravers, CNC machines, trainer rocker plates, and more.