All of my bantams are mailed Express Mail--all over the country and to Alaska. I do not mail baby chicks--most are about 4 mos old or older. Trios of 4 mos old birds can go in one box. A male with a great tail has a box to himself. Otherwise pairs can go together, but not if the hen is laying. And better not to send laying females--as going without water is VERY hard on the system, while producing eggs!! I would NEVER think of sending when temperatures are over 75f!!Both here and at their destination. It gets warmer in the box, especially if there are several birds in a box and if left on the tarmack for a while before loading on the planes, can get fierce, like in a parked car in 80+ degree temps. All of my April-June hatched chicks are not promised delivery until September, if cool enough. later, if necessary! Sometimes there are delays in airlines connections and the wonderful overnight delivery we used to have--seldom is possible. Last mailings, early June, have taken up to 4 days--cannot be hot--as I do put apples in the boxes, but 4 days without water during hot weather can be lethal! And proper boxes are a must! CJR