BEARINGDEX
Deep groove ball

6409 bearing

45 mm bore, 120 mm outside diameter, 29 mm width (1.7717 × 4.7244 × 1.1417 in).

Cross-reference 6409Decode a full part number

Dimensions

mminch
Bore d451.7717
Outside diameter D1204.7244
Width B291.1417

Quick numbers

Pitch diameter dm82.5 mm
Section height (D − d)/237.5 mm
n·dm at 1,800 rpm148,500
n·dm at 3,600 rpm297,000

Compare against the maker's limiting speed. Speed calculator · L10 life

What the number means

6Deep groove ball
4Diameter series 4: heavy. Width series 0 is implied and left off.
09Bore code 09 × 5 = 45 mm

How each brand writes it

Same bearing, every maker's notation
VersionSKFFAGNSKNTNKoyoNACHI
Open640964096409640964096409
Shields both sides6409-2Z6409-2ZR6409ZZ6409ZZ6409ZZ6409ZZE
Contact seals both sides6409-2RSH6409-2RSR6409DDU6409LLU6409-2RS6409-2NSE
Contact seals both sides, C36409-2RSH/C36409-2RSR-C36409DDUC36409LLUC36409-2RSC36409-2NSE C3 Verify
Non-contact seals both sides6409-2RSL6409-2BRS Verify6409VV6409LLB6409-2RU Verify6409-2NKE Verify
Shields both sides, C36409-2Z/C36409-2ZR-C36409ZZC36409ZZC36409ZZC36409ZZE C3 Verify