This listing is for 2 piece/s.A linear bearing, also known as a linear ball bush or bushing, is a bearing that runs on a hardened linear shaft to help guide or support the movement of a component in a linear fashion. A cost effective method of achieving linear motion where the loads are light enough to not need conventional linear guides or where the guide can only be supported at the ends and not over the entire length. Specifications Shaft diameter: 14 mm Closure type: Closed Bushing type: Ball Bushing Measurement standard: Metric Outside diameter: 21 mm Overall width: 28 mm Seal type: 2 Seals Lubrication: Linear Lube Load capacity: 830 N Operating temperature range: -30 to +80 °C Outer ring width: 28 mm Precision rating: Not Rated