<h3>Key features</h3><ul> <li>SBR12 LINEAR RAIL - This linear rail set includes 2 pieces of 800 mm/31.5 long SBR12 rail shafts and 4 SBR12UU blocks. Sliding blocksto be used cooperatively with rails, smooth sliding provided by inside linear bearing</li> <li>HIGH-QUALITY STEEL MATERIAL - Parts are made of carbon steel, with quality bearing steel linear bearings and aluminum alloy housing. Surface chrome plating treatment to be anti-rust, hardness can as high as HRC62, more durable</li> <li>STABLE LINEAR GUIDE SYSTEM -Perfect combination of main axle and aluminum support, which nicely stabilizes the original rail. Premier quality bearing blocks moves smoothly while using</li> <li>EASY TO INSTALL - Aluminum alloy support rail with pre-drilled holes for ease of mounting. Stainless steel Linear optical axis guide bearings linear movement. Easy to install, no need to maintenance.4 pieces SBR12UU Bearing Blocks afforded</li> <li>WIDE APPLICATION - lightweight design for easy to use.The linear guide rail is widely used in the automation machinery such as DIY CNC routers,lathes, machine tool, bending machines, laser welding machines, etc</li> </ul><p>Free shipping included. 30-day hassle-free returns.</p>