9900-1
Small Gear Wheels
Building instructions
The building instructions are on the official LEGO website. We do not host any instructions ourselves; the link below takes you to the official page.
View building instructions on LEGO.com (opens an external website)This set on Rebrickable (opens an external website)
Parts list – 9900-1 Small Gear Wheels
9 lines, 21 pieces
| Image | Part | Name | Colour | Quantity | Note |
|---|---|---|---|---|---|
 | 2983 | Motor Pulley, 9V Micromotor with Axle HoleElectronics | Light Gray | 2× | |
 | 4143 | Technic Gear 14 Tooth BevelTechnic Gears | Light Gray | 4× | |
![Part 4019 Technic Gear 16 Tooth with Round Holes [Old Style] in Light Gray](https://cdn.rebrickable.com/media/parts/ldraw/7/4019.png) | 4019 | Technic Gear 16 Tooth with Round Holes [Old Style]Technic Gears | Light Gray | 2× | |
![Part 3650c Technic Gear 24 Tooth Crown with Reinforcements [New Style] in Light Gray](https://cdn.rebrickable.com/media/parts/elements/365002.jpg) | 3650c | Technic Gear 24 Tooth Crown with Reinforcements [New Style]Technic Gears | Light Gray | 2× | |
![Part 3648b Technic Gear 24 Tooth [New Style with Single Axle Hole] in Light Gray](https://cdn.rebrickable.com/media/parts/elements/364802.jpg) | 3648b | Technic Gear 24 Tooth [New Style with Single Axle Hole]Technic Gears | Light Gray | 2× | |
 | 3647 | Technic Gear 8 ToothTechnic Gears | Light Gray | 3× | |
 | 3743 | Technic Gear Rack 1 x 4Technic Gears | Light Gray | 2× | |
 | 4716 | Technic Worm GearTechnic Gears | Black | 2× | |
![Part 4185 Technic Wedge Belt Wheel [aka Pulley] in Light Gray](https://cdn.rebrickable.com/media/parts/elements/4100502.jpg) | 4185 | Technic Wedge Belt Wheel [aka Pulley]Wheels and Tyres | Light Gray | 2× |