Measurement tokens are not officially supported by Figma. However, you can still create measurements in Figma by defining them in a specific frame.
👉 Have a look at our Figma example file to help you get started with measurement design tokens: https://www.figma.com/file/AwTS8rrCRHVdbtZlPkCvqN/?node-id=1%3A9.
To collect your measurements to Specify, you must have created a frame containing your measurements layers.
Specify will collect measurements based on:
The name of your layers for the name of your measurement
The width of your layers for the value of your measurement