# Timken 2MMC9103WI DUM Super Precision Angular Contact Ball Bearing, Duplex Medium Preload, P4S - MROSupply.com

***Timken 2MMC9103WI DUM is a super precision angular contact ball bearing configured as a duplex set with medium preload (DUM). This P4S (ABEC 7/9) class bearing is designed for high-speed, high-rigidity applications such as machine tool spindles, precision grinders, and jig borers. The duplex arrangement provides precise axial location and stiffness under combined loads.***



## Product details:

- Catalog number: 2MMC9103WI DUM
- SKU: 5081278
- Call for Pricing - 888-671-2883
- Shipping: ***FREE SHIPPING***  ON ORDERS OVER $100
- Typically Ships in: 1 day
- Brand: [Timken](https://www.mrosupply.com/brands/timken/)
- Category: 
    - [Single Row Angular Contact Bearings](htts://www.mrosupply.com/bearings/ball-bearings/angular-contact-ball-bearings/single-row-angular-contact-bearings/)
    - [Angular Contact Ball Bearings](htts://www.mrosupply.com/bearings/ball-bearings/angular-contact-ball-bearings/)
    - [Ball Bearings](htts://www.mrosupply.com/bearings/ball-bearings/)
    - [Bearings](htts://www.mrosupply.com/bearings/)
- Unit of measure: each
- Weight: 0.168 lb
- Returns: Yes


## Product images:
- https://static.mrosupply.com/images/noimage.webp


## Product attributes;

  
- 0.3937 in C0 - Static Radial Rating (per row): 3030 N
  

  
- 0.7874 in World part number: C7003C-T-P4S-DUM
  

  
- 0.850 in Limiting Speed (Grease) (per row): 51720 rpm Limiting speed (oil):103440 rpm Manufacturing part number:2MMC9103WI DUM O.D. (in):35 mm 1.378 Outer ring backing diameter:31.1 mm
  

  
- 1.230 in Rows per set: Duplex Total width:20 mm
  

  
- 1400 lbf Cage type: CR - Phenolic Outer Land Riding Cage Contact angle:15 Design units:Metric Inner ring backing diameter:21.5 mm
  

  
- 685 lbf C1 ISO - Dynamic Radial Rating (per row): 6220 N
  

  
- Ball type: Ceramic Bearing width:10 mm
  

  
- Ball Type: Ceramic
  

  
- Bearing Width: 10 mm 0.3937 in
  

  
- Bore: 17 mm
  

  
- C0 - Static Radial Rating (per row): 3030 N 685 lbf
  

  
- C1 ISO - Dynamic Radial Rating (per row): 6220 N 1400 lbf
  

  
- Cage Type: CR - Phenolic Outer Land Riding Cage
  

  
- Ce - Dynamic Radial Rating (per row): 6800 N 1530 lbf
  

  
- Contact Angle: 15 º
  

  
- d - Bore: 17 mm
  

  
- D - Outer Diameter: 35 mm 1.3780 in
  

  
- da - Inner Ring Backing Diameter: 21.5 mm 0.850 in
  

  
- Da - Outer Ring Backing Diameter: 31.1 mm 1.230 in
  

  
- Design Units: Metric
  

  
- DOuter Ring Backing Diameter: 31.1 mm 1.230 in
  

  
- Dynamic Radial Rating (per row): 6800 N 1530 lbf
  

  
- I.D.: 17 mm
  

  
- Inner Ring 'To Clear' Radius: 0.30 mm 0.012 in
  

  
- Inner Ring Backing Diameter: 21.5 mm 0.850 in
  

  
- Limiting Speed (Grease) (per row): 51720 rpm
  

  
- Limiting Speed (Oil): 103440 rpm
  

  
- Manufacturing Part Number: 2MMC9103WI DUM
  

  
- Outer Diameter: 35 mm 1.3780 in
  

  
- Outer Ring 'To Clear' Radius: 0.3 mm 0.012 in
  

  
- R - Inner Ring "To Clear" Radius: 0.30 mm 0.012 in
  

  
- r - Outer Ring "To Clear" Radius: 0.3 mm 0.012 in
  

  
- Rows per Set: Duplex
  

  
- Static Radial Rating (per row): 3030 N 685 lbf
  

  
- Total Width: 20 mm 0.7874 in
  

  
- World Part Number: C7003C-T-P4S-DUM
  
## Product documents / software:

- [Catalog](https://documents.mrosupply.com/product_documents/50/60/5060627/Machine-Tool-Applications-Catalog_R9rBZA3.pdf)

## Product's reviews:
- Best company to buy from - I always buy from MRO is a very reliable company to work with




## FAQ:

- How do I choose the right type of bearing for my application?: Start with the load and how it’s applied. You need to know if you’re dealing with radial loads, axial loads, or a mix of both. Then look at speed, operating environment, and space constraints.
For example, ball bearings are great for high speed and lighter loads, while roller bearings handle heavier loads but usually at lower speeds. If there’s contamination, moisture, or heat involved, you may need sealed bearings or specific materials.
In most cases, the right choice comes down to matching load type, speed, and environment to the bearing design.


- What is the difference between deep groove and angular contact ball bearings?: Deep groove ball bearings are the most common type. They’re designed to handle mainly radial loads, but they can also take some axial load in both directions. They’re simple, versatile, and used in everything from motors to conveyors.
Angular contact ball bearings are built for combined loads, especially where there’s significant axial force in one direction. They’re often used in pairs and are common in higher precision or higher load applications like pumps and gearboxes.
If your load is mostly radial, go deep groove. If axial load matters more, angular contact is usually the better choice.