# Boston Gear (Altra) - YD21 - Spur Gear, 20* pressure angle, 12 DP, 21 teeth, plain bore - Allied Electronics & Automation, part of RS Group

**Manufacturer:** Boston Gear (Altra)  
**MPN:** `YD21`

The Boston Gear YD21 Spur Gear is a steel component with an inch-based pitch of 12, a bore diameter of 0.750 inches, and an outside diameter of 1.917 inches. It features a face width of 1.000 inch and has 21 teeth.

## Specifications

| Attribute | Value |
| --- | --- |
| Brand name | Boston Gear (Altra) |
| Manufacturer name | Boston Gear (Altra) |
| Manufacturer | Boston Gear (Altra) |
| Category | Industrial Controls/Mechanical Power Transmission/Gears & Gear Racks/Gears |
| Extra Product Name | Boston Gear (Altra) - YD21 - Spur Gear, 20* pressure angle, 12 DP, 21 teeth, plain bore - Allied Electronics & Automation, part of RS Group |
| moq | 1 |
| MPN | YD21 |
| multiple | 1 |
| qtyInStock | 0 |
| SKU | 71839151 |
| snippet | Spur Gear, 20* pressure angle, 12 DP, 21 teeth, plain bore |

## Distributor availability

| Distributor | SKU | Price (USD) | Qty | Stock | MOQ |
| --- | --- | --- | --- | --- | --- |
| Allied Electronics | 71839151 |  |  | None | 1 |
| motionindustries.com | 00371802 | 62.87 | 1 | None | 1 |
| us.rs-online.com | 71839151 | 51.69 | 1 | 4 | 1 |

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