> For the complete documentation index, see [llms.txt](https://docs.revrobotics.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.revrobotics.com/ion-build/motion/gearboxes/2-motor-drivetrain-gearbox-through-bore.md).

# 2 Motor Drivetrain Gearbox - Through Bore

## Features

* Adjustable speed based on pinion gears
* Adjustable wheel size based on second stage gear pairs
* Mountable in a variety of options to allow for chain-in-tube and chain/belt outside tube designs

<figure><img src="/files/wuE82Ghfgpn3FPURO00D" alt=""><figcaption><p>2 Motor Drivetrain Gearbox - Through Bore</p></figcaption></figure>

### Kit Contents

| SKU             | DESCRIPTION                                                                                           | QTY. |
| --------------- | ----------------------------------------------------------------------------------------------------- | ---- |
| REV-21-2190-P01 | 2 MOTOR DRIVETRAIN GEARBOX MOTOR PLATE                                                                | 1    |
| REV-21-2190-P02 | 2 MOTOR DRIVETRAIN GEARBOX OUTPUT PLATE                                                               | 1    |
| REV-21-2190-P03 | 2 MOTOR DRIVETRAIN GEARBOX 1/2IN HEX CLUSTER SHAFT                                                    | 1    |
| REV-25-2489     | 2 MOTOR DRIVETRAIN GEARBOX SPACER PACK                                                                | 1    |
| REV-25-2488     | 2 MOTOR DRIVETRAIN GEARBOX HARDWARE PACK                                                              | 1    |
| REV-21-2079     | 1/2IN HEX THROUGH BORE SHAFT                                                                          | 1    |
| REV-21-2819     | [1/2 IN ROUNDED HEX SHAFT- 6.0IN LONG - TAPPED](https://www.revrobotics.com/.5in-Rounded-Hex-Shafts/) | 1    |
| REV-21-1916-PK2 | FLANGED BEARING FOR 1/2IN ROUNDED HEX - 2 PACK                                                        | 1    |
| REV-21-1937     | [20DP GEAR - 1/2IN HEX - 52T](https://www.revrobotics.com/20DP-Gears/)                                | 1    |
|                 | BEARING, 30MM ID, 42MM OD, 7MM THICK, SHIELDED, FLANGED - 2 PACK                                      | 1    |


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