No, items must not be locked under any circumstance. If your items are locked, the locks may be forcibly removed in transit or the collection may be refused collection or returned to you.
This is because for the majority of our shipments, they will undergo security/customs checks after collection.
If sending items with an internal lock, they must clearly appear unlocked - if your items appear locked, they will be assumed to be locked and may be removed or returned to you.
My Baggage is not responsible for damage to suitcases where locks have needed to be removed.
Don't worry however, your items are completely safe as they are sent within a closed couriers network.
If you do want to secure your items, we do recommend securing your suitcase with a cable or zip tie. As they can be easily accessed in the event of a customs inspection.
TSA locks are only valid for passengers on commercial flights to and from the USA where the TSA has authority.