DIY builders and makers, this 12mm miniature linear rail guide with an MGN12H sliding block is perfect for adding smooth, precise linear motion to your projects. Choose from various lengths (like 250mm, 300mm, up to 600mm) to fit your needs. It's a cuboid-shaped rail made for high accuracy in 3D printers, CNC routers, laser engravers, or other automated machines. The sliding block (carriage) rides on ball bearings for low friction and long life. Brand new, unbranded but solid quality. UPC: 808281812035, EAN: 0808281812035. Whether you're upgrading a printer or building something from scratch, this rail system offers professional-grade movement. Get your axes moving smoothly!