1.Complete Linear Rail Kits: This linear guide rail set includes 2 pieces of 66.9 in / 1700 mm long HSR20 rail shafts, 4 HSR20 bearing blocks, and a bunch of dust-proof plugs. 2.High-Quality Steel Material: The linear motion slide rails are made of high-quality 55C steel, and blocks are made of GCr15 ball bearing steel and PA66, an excellent non-conductor. The durable kit will endure through time. 3.Premier Linear Guiding System: The linear slide guide rail provides a smooth and precise sliding surface for the bearing blocks. It helps to build an economical linear guiding system and is designed to achieve high precision linear motion, low friction coefficient. 4.Easy to Install: The linear bearing set has holes pre-drilled for ease of fixation. It's easy to install and meet all your needs for many different machines. What's more, it generally does not need to maintain. 5.Wide Application: The linear guide rail is widely used in CNC Router/CNC Grinding machines, industrial machinery printing, paper-processing, automatic machine, X-Y table, factory automation equipment, etc. ******************************************************************************************************* *Specifications Type: Linear Actuator Rail Shafts: HSR20, 66.9 in / 1700 mm Gross Weight: 20 lbs / 9.1 kg Package Dimensions: 67.3 x 3.5 x 3.1 in / 171 x 9 x 8 cm ******************************************************************************************************* *Pakcage Content 2 x HSR20-1700 mm Linear Slide Guide Rails 4 x HSR20 Bearing Blocks 1 x Set of Dust-Proof Plugs