There are three types of loans in Ebook Central: Admins can set whether users are prompted before a loan is triggered, either for all loans or only for STL on DDA.

For each type of loan, admins can set a fixed duration for all loans of that type, or admins can set optional loan lengths and let the user decide which loan length they would like.  For users to be able to choose the loan length, prompting needs to be turned on.  (If the admin has set loan-length options, but prompting is not turned on, the loan will default to the shortest duration indicated.)

To set whether users are prompted before an NL loan or an STL for Extended Access or DDA is triggered:

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The radio-button settings mean the following:
To set the duration options for NL loans:
To set the STL duration options for both DDA and Extended Access:
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