Is there a way to create a time slot, similar to when you add a calendar a pop up appears and you can choose a date. I've aded a screenshot of what I've created, which is a single select option, But would like it to be more flexible. So, if you choose 9am it will autofill a a two hour duration, 9-11 or if you chose 8am it will autofill 8-10 am.

Thanks. 

le.