Item Type: Square Flange Linear Ball Bearings Model: LMK20UU Shaft Diameter: Approx. 20mm / 0.79in Outer Diameter: Approx. 32mm / 1.26in Length: Approx. 42mm / 1.65in Material: Bearing steel Package List 2 x Square Flange Linear Ball Bearings Requires regular cleaning and maintenance. 1SMALL LOAD WITH MINIMAL RESISTANCE: Square flanged linear ball bearings are a low cost production linear motion system for use with cylindrical shafts with infinite travel. Since the bearing ball is in point contact with the shaft, the operating load is small. The steel ball rotates with minimal frictional resistance, resulting in a smooth motion with high accuracy 2ACCURATE AND FAST: Linear bearings are used in conjunction with quenched linear drive shafts to make infinite linear motion systems. Because the load balls and quenched drive shafts are in point contact, the allowable load is small, but during linear motion, the friction resistance is the smallest, possess high accuracy and fast movement 3EASY TO REPLACE: The bearing block has a certain bearing capacity, can be installed on the ordinary accuracy rack, and has strong adaptability. The linear guide shaft support has low friction resistance, can obtain high accuracy rotation in smooth motion, and is easy to maintain and replace 4LOW NOISE AND HIGH RIGIDITY: The bearing steel ball forms a complete closed loop, which makes the raceway super accuracy and improves the bearing stability, with low noise, stable movement, low friction, high rigidity, smooth operation and long service life 5WIDELY USED: Guide rail brackets are widely used in digital 12D coordinate measuring equipment such as accuracy equipment or special machinery industries, and are suitable for various electronic equipment, guide rods and columns