Special Service Requests (SSR) such as meal requirements, wheelchair assistance, and other similar requests. "Optional Services Instruction" or "Other Service Information" (OSI) - information sent to a specific airline, or all airlines in the booking, which enables them to better provide a service. This information can include ticket numbers, local contacts details (the phone section is limited to only a few entries), airline staff onload and upgrade priority codes, and other details such as a passenger's language or details of a disability.