Welcome to our store！</br> 1、The bearing shaft is specially designed and suitable for 3D printer, made of high‑quality ABS material, which is durable. 2、This bearing can effectively reduce vibration and unnecessary noise,and if you add lubricant and use it, you will get great smoothness. 3、The bearing is particularly suitable for small manufacturing machines such as 3D printers, but suitable not for large machines. 4、The size is the same as the standard recirculating ball bearing, and the assembly can be easily completed by just pressing lightly by hand. 5、The bearing shafts has a wide application, which are widely used in for RepRap / Mendel and other 2 x 3D printer bearings. <p class="wang-edit-text"><p class="wang-edit-text"> Item Type: Bearing Shafts Material: Plastic Model: LM12UU Outer Diameter: 21 mm / 0.82 in Inner Diameter: 12mm / 0.47 in Length: 30mm / 1.18 in <style> .wang-edit-text{ font-family:'Arial' !important; } .wang-edit-text table { border-top: 1px solid #000; border-left: 1px solid #000; } .wang-edit-text table td, .wang-edit-text table th { border-bottom: 1px solid #000; border-right: 1px solid #000; padding: 3px 5px; } .wang-edit-text table th { text-align: center; }</style> 4 x Bearing&nbsp;Shafts Satisfaction - Our customers are our top priority. If you find any product problems after receiving the goods, such as damage and incorrect quantity of goods, please contact the seller immediately. We try our best to provide you with satisfactoryaftersalesservice</br>