# Set variables shape
## Introduction
The **set variables** shape is used to set values for flow variables and/or metadata variables at any point in a flow.
## Need to know
When defining variable values you can use:
* static text (e.g. `blue-003`)
* [payload syntax](https://doc.wearepatchworks.com/product-documentation/process-flows/building-process-flows/dynamic-variables/payload-variables) (e.g. `[[payload.productColour]]`)
* [flow variable syntax](https://doc.wearepatchworks.com/product-documentation/process-flows/building-process-flows/dynamic-variables/flow-variables) (e.g..`{{flow.variables.productColour}}`)
{% hint style="info" %}
A single incoming payload for [any process flow shape](https://open.gitbook.com/~site/site_dIV1g/~/revisions/9dTvdvRJIRVZQXuBMMnJ/process-flows/building-process-flows/process-flow-shapes) should not exceed 500MB.
We recommend processing multiple, smaller payloads rather than one single payload (1000 x 0.5MB payloads are more efficient than 1 x 500MB payload!).
For payloads up to 500MB, consider adding a[ flow control shape](https://open.gitbook.com/~site/site_dIV1g/~/revisions/9dTvdvRJIRVZQXuBMMnJ/process-flows/building-process-flows/process-flow-shapes/standard-shapes/flow-control-shape) to batch data into multiple, smaller payloads. Payloads exceeding 500MB should be batched at source.
{% endhint %}
## Adding & configuring a set variables shape
**Step 1**\
In your process flow, add the **set variables** shape in the usual way:
**Step 2**\
Access shape settings:
**Step 3**\
Click the add new variable option associated with the type of variable that you want to define - for example:
**Step 4**\
Options are displayed for you to define the required variables and their values. How these are displayed depends on the type of variable you've chosen to add:
Variable (flow variables)
Choosing to add a **variable** displays a **flow variable** drop down field:
From here you can select any [flow variable that's been defined for this process flow](https://doc.wearepatchworks.com/product-documentation/process-flows/building-process-flows/dynamic-variables/flow-variables) - for example:
You then define the required values to be applied, and confirm with the **accept** button:
Meta (payload metadata variables)
Choosing to add a meta variable displays **key** and **value** fields:
From here you define your variable name as the **key** and set the the required **value** to be applied - then confirm with the **accept** button:
**Step 5**\
Once variables are accepted they're added to the settings panel (you can edit/delete as needed):
Variable (flow variables)