@Milo James Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
Adding more information to the above answe : A shared access signature (SAS) is a URI that grants restricted access to an Azure Storage container. Use it when you want to grant access to storage account resources for a specific time range without sharing your storage account key. Learn more
You can also create a shared access signature (SAS) using a stored access policy through Azure Storage Explorer, please refer to this Q&A thread
Additional information: Refer to the following links: Delegate access with a shared access signature
Hope this helps!
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