NTN MRC.308M

Deep groove ball · Open

The seat — 40 MM × 90 MM × 23 MM

Bore

40 MM

Outside dia

90 MM

Width

23 MM

Type

Deep groove ball

Seal

Open

Clearance

CN (Normal)

Precision

ABEC-1 (P0)

Dynamic C

45.7 kN

Static C0

36.0 kN

158 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 — 25 designations · top 20 shown

Part number	Manufacturer	C	C0
308	NTN	45.7 kN	36.0 kN
308-ZNR	NTN	45.7 kN	36.0 kN
308 NR	NTN	45.7 kN	36.0 kN
MRC.308MF	NTN	45.7 kN	36.0 kN
MRC.308MFF	NTN	45.7 kN	36.0 kN
MRC.308MFG	NTN	45.7 kN	36.0 kN
MRC.308MG	NTN	45.7 kN	36.0 kN
6408	NTN	43.6 kN	24.3 kN
308K	Timken	42.3 kN	24.0 kN
6308	NTN	42.3 kN	24.0 kN
6308-2RZ	NTN	42.3 kN	24.0 kN
6308-ZNR	NTN	42.3 kN	24.0 kN
6308 JEM	NTN	42.3 kN	24.0 kN
6308 N	NTN	42.3 kN	24.0 kN
6308 NR	NTN	42.3 kN	24.0 kN
6308 NRJEM	NTN	42.3 kN	24.0 kN
6308 RSJEM	NTN	42.3 kN	24.0 kN
6308 ZJEM	NTN	42.3 kN	24.0 kN
MRC.308S	NTN	42.3 kN	24.0 kN
MRC.308SFF	NTN	42.3 kN	24.0 kN

Check before substituting — 133 designations · top 12 shown

Part number	Manufacturer	C	Differs from this part
21308 E	NTN	107.0 kN	Type: Spherical — this part: Deep groove ball
21308 E/C3	NTN	107.0 kN	Type: Spherical — this part: Deep groove ball Clearance: C3 — this part: CN (Normal)
21308 EKW	NTN	107.0 kN	Type: Spherical — this part: Deep groove ball
21308 EW	NTN	107.0 kN	Type: Spherical — this part: Deep groove ball
21308 EW/C3	NTN	107.0 kN	Type: Spherical — this part: Deep groove ball Clearance: C3 — this part: CN (Normal)
N 308 ECM	NTN	93.0 kN	Type: Cylindrical — this part: Deep groove ball
N 308 ECP	NTN	93.0 kN	Type: Cylindrical — this part: Deep groove ball
N 308 ECP/C3	NTN	93.0 kN	Type: Cylindrical — this part: Deep groove ball Clearance: C3 — this part: CN (Normal)
NJ 308 ECJ	NTN	93.0 kN	Type: Cylindrical — this part: Deep groove ball
NJ 308 ECJ/C3	NTN	93.0 kN	Type: Cylindrical — this part: Deep groove ball Clearance: C3 — this part: CN (Normal)
NJ 308 ECM	NTN	93.0 kN	Type: Cylindrical — this part: Deep groove ball
NJ 308 ECML	NTN	93.0 kN	Type: Cylindrical — this part: Deep groove ball

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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