Our parts warranty process ID90 checks 3 conditions - if a part meets days, click yield and core return.
This "Returnable" box is supposed to identify items that should be returned to the vendor for a credit, for example a board that must be returned otherwise you will be charged an additional amount.
If you have a lot of items and unsure if its been used correctly, rather than research we suggest you have CEOJuice reset all these to Nil to start with a clean slate. To request this email email@example.com
More details on ID90 here