Descriptions: linear slide shaft is made of quality carbon steel, and bearing block is made of aluminum alloy, sturdy and . for your DIY CNC routers, no more unwanted errors in your machining work mills, lathes. Features: linear slide shaft is made of quality carbon steel, and bearing block is made of aluminum alloy, sturdy and . Industrialgrade- standard SBR block, with linear bearing inside. silver plating care, beautiful antirust-, hardness can as as HRC62, more . adjusting handle can adjust tightness of slider. Standardized processing, ideal for positioning. for your DIY CNC routers, mills, lathes. Aluminum alloy support with predrilled- holes for ease of mounting. Specifications: Material: carbon steel, Aluminum alloy Model: SBR12 shaft length: 400mm / 1575inch. shaft diameter: 12mm / 047inch. Block inner diameter: 12mm / 047in. Block outer diameter: 40mm / 157in. Weight1900g: Package Included: 2 x Linear Slide Shaft 4 x Bearing Slide Block