1、GOOD STABILITY: Including linear motion guide rail and external biaxial linear guide slide block, has stable structure, low friction and smooth sliding. 2、EXCELLENT MATERIAL: Made of bearing steel and aluminum alloy materials, with fine workmanship, wear and corrosion resistant, has long service life. 3、EASY TO INSTALL: The linear rail slide block has 8 mounting holes, with 4 pulleys, can install the components you want to install in any combination. 4、WIDE APPLICATION: Used in semiconductor manufacturing, printed circuit board, IC packaging, medical equipment, robotic arm and fine encoder, etc. 5、FOR LINEAR DEVICE: The total length of the linear guide rail is 300mm, can be used for small linear motion devices, has a wide range of applications. 1 x Slide Block  1 x Guide Rail Item Type: Linear Guide RailMaterial: Bearing Steel, Aluminum AlloyNumber of Slider Mounting Holes: 8Number of Pulleys: 4Guide Rail Total Length: Approx. 300mm / 11.8in