I'm not sure exactly what you are asking, but it sounds like what you'll want to use is a List. Have the different items in the rack push themselves to a list. And then when you pull them from the rack, Pull from the list, using a query to select the item you want. "Age" is a default value on item lists that designates the time the item has been on the list, but you could add your own labels (such as the date and time) to the item, and then have that as a field on the list as well. Then you can query for the item using date/time.
If you haven't used Lists before, the documentation in the manual can give you a good basis to start with. There are also some tutorials and examples you can find in the manual and here on Answers. https://answers.flexsim.com/articles/22945/list-examples-6.html
