Carry-on luggage should weigh less than 10 kg in total, and should be no more than 1 meter in length and 0.027m3 in capacity.
The carry-on luggage has to be able to fit into the overhead rack or under your seat.
Note: In some cases, there are heaters below your seat, which may cause that space to heat up considerably.
In some cases, the check-in crew or the bus driver may ask you to put your carry-on luggage in the trunk.