NTN 3309 A

Angular · Open

The seat — 45 MM × 100 MM × 39.70 MM

Bore

45 MM

Outside dia

100 MM

Width

39.70 MM

Type

Angular

Seal

Open

Clearance

CN (Normal)

Precision

ABEC-1 (P0)

Dynamic C

75.0 kN

Static C0

53.0 kN

19 other designations in the catalogue share this bore × outside diameter × width. Each was compared on the four fields every bearing row carries — Type, Seal, Clearance, Precision — as recorded, case- and separator-insensitively. All four agreeing puts a designation in the first list; anything else, a difference or a blank, puts it in the second with the fields named.

Candidates at the recorded dimensions above

May substitute — 5 designations

Part number	Manufacturer	C	C0
3309 ATN9	NTN	75.0 kN	53.0 kN
MRC.5309C	NTN	75.0 kN	53.0 kN
MRC.5309CFF	NTN	75.0 kN	53.0 kN
3309 ANR	NTN	71.5 kN	53.0 kN
MRC.5309CG	NTN	71.5 kN	53.0 kN

Check before substituting — 14 designations · top 12 shown

Part number	Manufacturer	C	Differs from this part
3309 A-2RS1	NTN	75.0 kN	Seal: 2RS contact seal — this part: Open
3309 A-2RS1/C3	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)
3309 A-2RS1/C3MT33	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)
3309 A-2RS1/MT33	NTN	75.0 kN	Seal: 2RS contact seal — this part: Open
3309 A-2RS1TN9/C3MT33	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)
3309 A-2Z	NTN	75.0 kN	Seal: 2Z shield — this part: Open
3309 A-2Z/C3	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)
3309 A-2Z/C3MT33	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)
3309 A-2ZTN9/C3VT113	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)
3309 A-Z/C3	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)
3309 A/C3	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)
3309 ATN9/C3	NTN	75.0 kN	Clearance: C3 — this part: CN (Normal)

What this sheet is — and what the catalogue did not say

The envelope is recorded dimensions only: the same bore, outside diameter and width. Every designation above shares all three, or it would not be on this page.
The four compared fields are Type, Seal, Clearance, Precision. Two recorded spellings were counted to mean one value and are read as one: CN/Normal = CN, and ABEC-1/P0 = P0. A third precision spelling, P0/Class4, is deliberately not equated with either — the catalogue's meaning for it has not been sourced, so it lands in the warnings where both spellings are printed for the reader to judge.
A blank is a difference. Missing is the absence of the proof, not the proof.
Cage material and ring material are never compared: the catalogue records neither, on any bearing row.
Suffixes the catalogue does not record separately — a snap ring (NR) and anything else outside those four fields — are not compared, and this sheet does not claim they match.
Ranking is recorded dynamic load, strongest first, with an unrecorded rating ranked last. It orders the lists; it is not a verdict.
Compiled from catalogue records. This is not a manufacturer interchange list, no manufacturer has confirmed any line on it, and it does not know what job the bearing is doing. Verify before fitting.

Anyone with this link can view this part and its recorded candidate comparison.

BEARINGBRAIN.COM/PART/3309A/SUBSTITUTE