"You can still choose to bring one slightly bigger bag up to the maximum size of 56cm x 45cm x 25cm including handles and wheels, but on some busy flights your bag may have to go into the hold." ...

23kg (51lbs), up to 56×45×25cm (22 x 18 x 10in) 1 handbag or laptop bag ... Maximum dimensions of the trolley bag: 55 x 40 x ...