Full explanation
SKF/FAG/NSK designations per ISO 15: series 6 — deep-groove ball (6205, 6305), series 3 — tapered roller (30208, 32216), series 4 — double-row ball. Six-digit base code: 6205-2RS/C3 means deep-groove series 6, size 52×25×15 mm, 2RS sealing (two rubber seals), C3 radial clearance. Genuine SKF/FAG/NSK/Timken — UAH 250–850 for common 6205/6305 (April 2026). Russian/Belarusian cheap GPZ/ZVL — UAH 80–150, service life 30–50%. Chinese NSK copies from AliExpress — ~25% of life. Critical agri-machinery applications: PTO joints, combine reduction gears, rotary mowers, grain-auger shafts — Tier 1 quality required. L10 life: L10 = (C/P)³ × 10⁶ revolutions.