1Brand new and high quality. 2Made of bearing steel material, these linear guide rails and blocks are durable. 3Designed with longitudinal grooveon the surface, which is used to fix and guide the parts of the machine, instrument, etc. 4They have high precision, wear-resistance, the surface is smooth and not easy to rust. 5Widely used for textile machinery, printing machinery, electric equipment, medical machinery, precision machine tools and more.Features: Brand new and high quality. Made of bearing steel material, these linear guide rails and blocks are durable. Designed with longitudinal grooveon the surface, which is used to fix and guide the parts of the machine, instrument, etc. They have high precision, wear-resistance, the surface is smooth and not easy to rust. Widely used for textile machinery, printing machinery, electric equipment, medical machinery, precision machine tools and more. Specification:Material: Bearing steel Rail Length: 300nn Rail Width: 20mm Rated Static Load: 25.31 Fixed Bolt Size: M4*16mm Allowable Static Moment: 0.17kN.m Package Weight: 816g/28.8oz Package List:1 x Linear Guide Rail 2 x Slider