Please note that extra baggage is accepted only if space is available on the aircraft. (American) a cheque. Legal. a ticket received in return for handing in baggage etc. The maximum weight for checked baggage is based on the class of service and on the traveler's MileagePlus Premier status at the time of check-in. Active U.S. Oversized baggage Baggage with total outer dimensions (length + width + height) measuring more than 115 inches (292 cm) will not be accepted as checked baggage. Idioms. (32 kg) MileagePlus Premier members Travel companions of MileagePlus Premier members will have the same exemptions as the Premier member whose status provides the benefit, as long as they are traveling on the same reservation.