Collections can be locked to only allow requests of a specified type to be added.

Locking a Collection to a specific request type has several benefits including allowing ASIN Data API to automatically choose the correct CSV fields, appropriate to the requests in the Collection, to be selected by default when exporting a Result Set in CSV mode. It can also help organize your account when you have many Collections set up.

A Collection can also be left unlocked (set to mixed ) to allow any request type to be added.

If you leave the Collection as unlocked ASIN Data API will automatically detect the request type based on the requests that have been subsequently added to the Collection (or will be set to mixed in the case of the Collection containing a mix of different request types).

You can specify whether a Collection is locked when setting the Collection up in the Dashboard, or via the Collections API. For more information see the Create Collection API documentation.