<h3>Key features</h3><ul> <li>Size and PackingLM12UU Bore Diamter (ID): 12mm, Outer Diameter (OD): 21mm, Total Length (L): 30mm. Package include 4 PCS bearings</li> <li>Material Made of bearing steel material,Static load rating of 784/C0 N and dynamic load rating of 510/CN, Double Side Rubber Seal Linear Motion Ball Bearing Bushing, Double Side Rubber Seal</li> <li>High Precision4 lines steel ball is in point contact with the shaft and rotates with very little frictional resistance, so as to obtain smooth movement with high precision.</li> <li>Performance Smooth moving, low friction, low noise, high rigidity and long life. Economical, easy to maintain replace.</li> <li>Application Suitalbe for kinds of electronic equipment/guide bar, and pillar, 3D printers and CNC machines.</li> </ul><p>Free shipping included. 30-day hassle-free returns.</p>