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KOYO Needle Roller Bearing: M-1, 661, 3/8 in Bore, 9/16 in OD, Full Complement - Drawn-Cup Needle Roller Bearings
KOYODrawn-Cup Needle Roller Bearings

KOYO Needle Roller Bearing: M-1, 661, 3/8 in Bore, 9/16 in OD, Full Complement

The KOYO M-1 is a drawn-cup needle roller bearing, part number M-661, with a single row and full complement of rollers. It has a 3/8-inch bore and a 9/16-inch outer diameter, is open and made of alloy steel, and uses…

SKU 3G-OTH-103558

Also listed as: M661 · M 661

Brand
KOYO
Item
Needle Roller Bearing: M-1, 661, 3/8 in Bore, 9/16 in OD, Full Complement
Category
Drawn-Cup Needle Roller Bearings
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Local availability & support

Delivery
Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment
Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

KOYO
Manufacturer Part Number
M-661
Type
661, Full Complement, Open, Alloy Steel
Bore
3/8 in
OD
9/16 in
Bearing Design
M-1
Number of Rows
One
Full Complement
Yes
System of Measurement
Inch
Bearing Industry Number
661

Technical Documents

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KOYO Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The KOYO M-1 is a drawn-cup needle roller bearing, part number M-661, with a single row and full complement of rollers. It has a 3/8-inch bore and a 9/16-inch outer diameter, is open and made of alloy steel, and uses inch-system measurements.

Frequently Asked Questions

What is the KOYO M-661 needle roller bearing used for?

The KOYO M-661 drawn-cup needle roller bearing is used in applications requiring high load capacity in a compact radial space, such as automotive transmissions, gearboxes, and industrial machinery. Its full complement design maximizes roller count for higher load ratings.

What are the specifications of the KOYO M-661 bearing?

The KOYO M-661 is a single-row, full-complement drawn-cup needle roller bearing with a 3/8-inch bore and 9/16-inch outer diameter. It is open, made of alloy steel, and uses inch-system measurements. The bearing design is M-1 with industry number 661.

Where to buy KOYO M-661 bearings worldwide?

KOYO M-661 bearings are available to order through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time.

How to select the correct KOYO drawn-cup needle roller bearing?

To select the correct KOYO drawn-cup needle roller bearing, verify the bore size (3/8 in), outer diameter (9/16 in), and system of measurement (inch). Ensure the bearing design (M-1) and full complement configuration match your application's load and speed requirements. Consult KOYO specifications for fit and tolerance.

Used in

Common applications for KOYO
Automotive transmissions — KOYO drawn-cup needle roller bearings (B-44) for gear support in compact gearbox assemblies.
Conveyor systems — KOYO heavy-duty needle roller bearings (HJ-202820) for radial load handling in roller conveyors.
Printing machinery — KOYO needle roller thrust bearings (NTA-3648) for axial positioning of rotating cylinders.
Industrial pumps — KOYO thrust bearing washers (TRD-3648) for axial load distribution in pump shafts.
Indexing tables — KOYO single-direction clutch and bearing assemblies (FCB-20) for precise indexing and overrunning control.
Material handling equipment — KOYO drawn-cup needle roller bearings (BH-2020) for compact wheel or roller supports.

KOYO Products

3G Electric supplies KOYO drawn-cup needle roller bearings. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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