How to understand after-sales parts

After-sales service express. After-sales refers to the behavior after the completion of the commodity sales transaction process. After-sales parts are express parts of after-sales service, including return and maintenance. Express delivery, also known as express delivery or express delivery, refers to a new mode of transportation in which logistics enterprises deliver documents or packages entrusted by users from the sender to the recipient's door quickly and safely through their own independent networks or in the form of joint ventures.