Miniature Linear Guide Rails, MGN12H Black Mini Rail 250/300/ 400/500/ 550mm Sliding Gide with Carriage Block for DIY 3D Printer and CNC Machine(300mm)

【EXCELLENT LINEAR GUIDE BLOCK】- This linear rail and block are small in size and lightweight, especially suitable for small equipment. 【HIGH STRENGTH】- Adopting 4-point contact design, it can bear the load from every direction and has good strength and high accuracy. 【SIZE】- Width: 12mm / 0.5in; Length: 300mm / 11.8in; Lockout method: locked 【NICE PERFORMANCE】- Designed with ball stop, which allows interchangeability in case of allowable accuracy. The slide block is designed with mini steel holding wire and the steel ball will not fall off if you pull out the slide block. 【APPLICATION】- Widely used for automatic equipment, precision measuring instruments and many other machines that require precision linear motion.