Single-row deep groove ball bearings are the most common bearing type in the world due to their versatility and performance. These bearings are available in a variety of seal, shield and snap-ring arrangements. Bearings with seals or shields are standardized and already contain the proper amount of grease. Open bearings will require lubrication. These bearings can sustain radial and/or axial loads and because of their simple design, this bearing type can be produced to provide both high-running accuracy and high-speed operation. NACHI Miniature Deep Groove Ball Bearing, 1/2 in Bore, 1-1/8 in OD, 1 Row, 1/4 in Width, Open Closure, 1149 lb Dynamic/511 lb Static Load, Steel Bearing, Machined Bronze Cage, 27000 RPM Grease/32000 RPM Oil Maximum, 250 °F