Linear motion bearings are special bearings designed to reduce  friction in different reciprocating units and mechanisms. Constructively,  linear motion bearings can be designed for unlimited or for limited  reciprocating motion. Their rolling elements can be both balls and rollers  (needle or cylindrical). Linear motion bearings can be supplied with protective  contact seals or without them.
  
                              They are used in robotics, woodworking, machine tool industry and  many other branches of mechanical engineering. 
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