Linear Ball Slide SBR-UU&SBR-LUU SBR Linear motion ball slide units
https://www.hyballscrew.com/product/sbr-rail/sbruu-sbrluu-sbr-linear-motion-ball-slide-units.html
Linear Motion Ball Bearing widely used in industrial, home and hobby appliances, low noise and high speed electric motors, construction machinery, automotive components, pumps, and machinery.