The SKF 6309 is an open deep groove ball bearing (unsealed), featuring a 45mm inner diameter, 100mm outer diameter, and 25mm thickness. Made of high-carbon chromium steel (GCr15) with a pressed steel cage, it suits medium-speed, heavy-load applications (e.g., heavy machinery, mining equipment, large electric motors). It handles radial and bidirectional axial loads, offering high strength, low friction, and long service life.