Not a mailing bag
Wardrobe boxes include a plastic rail so suits, dresses, trousers and jackets hang. The category states sizes as internal dimensions.
A padded envelope or a poly mailer will not do that job. The garment box is its own line, even though it can be ordered with paper, tape and fill.
Dispatch
An order placed by 3pm leaves that day. UK delivery is free over £50 ex VAT.