NSK 6304DDU

Deep groove ball · 2RS contact seal

The seat — 20 MM × 52 MM × 15 MM

Bore

20 MM

Outside dia

52 MM

Width

15 MM

Type

Deep groove ball

Seal

2RS contact seal

Clearance

Precision

ABEC-1 (P0)

Dynamic C

15.9 kN

Static C0

7.8 kN

94 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 — 21 designations · top 20 shown

Part number	Manufacturer	C	C0
6304-2RSH/VA947	NTN	16.8 kN	7.8 kN
6304-2RSHNR	NTN	16.8 kN	7.8 kN
6304-2RSL	NTN	16.8 kN	7.8 kN
6304-RSH	NTN	16.8 kN	7.8 kN
6304 2RSJEM	NTN	16.8 kN	7.8 kN
6304 2RSNRJEM	NTN	16.8 kN	7.8 kN
6304.2RSR	FAG (Schaeffler)	16.1 kN	7.9 kN
6404.2RSR	FAG (Schaeffler)	16.1 kN	8.4 kN
304PP	Timken	15.9 kN	7.8 kN
6304-2RS	KOYO (JTEKT)	15.9 kN	7.8 kN
6304-2RS1	NTN	15.9 kN	7.8 kN
6304-2RSH	NTN	15.9 kN	7.8 kN
6304-2RSR	FAG (Schaeffler)	15.9 kN	7.8 kN
6304LLU	NTN	15.9 kN	7.8 kN
6404-2RS1	NTN	15.9 kN	8.3 kN
63042RS	Timken	15.7 kN	7.7 kN
64042RS	Timken	15.7 kN	8.2 kN
6404DDU	NSK	15.6 kN	8.1 kN
6404LLU	NTN	15.4 kN	8.1 kN
W 6304-2RS1	NTN	13.8 kN	7.8 kN

Check before substituting — 73 designations · top 12 shown

Part number	Manufacturer	C	Differs from this part
N 304 ECP	NTN	35.5 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal
NJ 304 ECP	NTN	35.5 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal
NJ 304 ECP/C3	NTN	35.5 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal Clearance: C3 — this part: CN
NU 304 ECP	NTN	35.5 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal
NU 304 ECP/C3	NTN	35.5 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal Clearance: C3 — this part: CN
NUP 304 ECP	NTN	35.5 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal
QJ 304 MA	NTN	32.0 kN	Type: Angular — this part: Deep groove ball Seal: Open — this part: 2RS contact seal
QJ 304 N2MA/C2L	NTN	32.0 kN	Type: Angular — this part: Deep groove ball Seal: Open — this part: 2RS contact seal Clearance: C2 — this part: CN
NU 304.M1	FAG (Schaeffler)	23.6 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal
NU 304	Timken	23.2 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal
NU 304 EM	NTN	22.7 kN	Type: Cylindrical — this part: Deep groove ball Seal: Open — this part: 2RS contact seal
7304 ACCBM	NTN	20.8 kN	Type: Angular — this part: Deep groove ball Seal: Open — this part: 2RS contact seal

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.

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