Product details
- Brand
- Humanscale
- Color / finish
- Black
- Product type
- Under-desk keyboard tray with right-side swivel mouse platform
Description
The 900 platform provides a dedicated keyboard surface while the 12R places the mouse on a separate round area to the right. This arrangement preserves keyboard space and lets the mouse support swivel within the system’s design. The 6G mechanism adjusts typing height and platform angle independently.
This is the 12R configuration described by the product title and feature list. Humanscale identifies 12R as the 10-inch right-side swivel platform; the smaller 11R eight-inch option is a different configuration. Confirm the combined layout works with your chair arms, desk opening and keyboard before ordering.
Features
- 900 keyboard board: provides a 19-inch-wide surface for a compatible keyboard.
- 6G mechanism: offers independent height and tilt adjustment.
- 12R mouse surface: adds a 10-inch swivel platform on the right.
- Gel palm support: provides a 19-inch support covered in synthetic leather.
- Sliding track: allows the assembly to move inward when adequate under-desk clearance is available.
Specifications
| Keyboard platform | 900 Standard |
|---|---|
| Platform dimensions | 19 W × 10.625 D in |
| Arm mechanism | 6G |
| Mouse platform | 12R: 10-inch swivel, right side |
| Palm support | 19-inch gel with synthetic-leather cover |
| Tilt adjustment | 0° to −15° |
| Track | Standard nominal 22-inch track; check supplied hardware dimensions |
| Color | Black |
Plan a comfortable fit under the desk
Start with the keyboard close enough that reaching does not pull you away from the chair. Adjust height and tilt in small steps, then position the mouse where it is easy to reach. A palm support is most useful as a resting surface between active typing movements.
| Keyboard size | Check the keyboard housing against the 19-inch board width, including protruding keys or controls. |
|---|---|
| Right-side mouse area | Allow room for the separate 10-inch platform beside the keyboard board. |
| Mounting surface | Inspect the underside for drawers, aprons and frame members before locating the track. |
| Chair approach | Check that armrests and knees clear the assembly in your normal seated position. |
Common questions
Is the mouse platform 8 or 10 inches?
This listing specifies 12R, the 10-inch right-side swivel option. The 11R designation refers to a different eight-inch platform.
Can I order this as a left-hand system?
This product is the right-side 12R configuration. A left-side system uses a different component specification and should be selected separately.
Does the gel rest include a keyboard?
No. The gel palm support is an accessory on the tray system. A keyboard and mouse are not specified as included.
Will it retract beneath every desk?
Only if the track, arm and platform have enough clear space. Measure underside depth and check for crossbars, drawers and cable-management hardware before installation.
Product information & sources
The manufacturer guide identifies 12R as the 10-inch right-side swivel platform. Verify the supplied track dimensions and installation clearance for the intended desk. Humanscale: adjustable keyboard-system overview; Humanscale: 900 board, 12R mouse platform and gel support codes. Reviewed September 2026.
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