Gearboxes are complex items which are common components of automated buildings. Each gearbox is individually designed on a Gearbox Assembly Table using a combination of small, medium and large gears.
The Gearbox Design tech is needed to design gearboxes.
Each individual gearbox is named according to its "outputs", of which it can have between 1 and 3. Outputs are identified by a letter (A through H), representing the output's location on the gearbox; and a number, representing the output's rotation speed. An example of a 2-output gearbox might be "Gearbox: B268 F133".
Buildings and techs requiring gearboxes will generally specify a range of acceptable output numbers that will fulfill the gearbox requirement. For example, a building may require "Gearbox: B200-B299", and any 1, 2, or 3-output gearbox with a B output of speed between 200 and 299 will suffice.
The characteristics of a gearbox are determined by its design. See the Gearbox Design guide for more on how to design gearboxes.
Gearboxes used in quarries are retrievable. Quarries can use both single-output (marble mechanics) and dual-output boxes (advanced marble mechanics). There are two things to consider when making gearboxes for quarrying.