Six airports

Right.

Hotel fridge froze everything on the first night. Second night: rolled towel, minibar off, thermometer in. Fine.

Forty-one degrees and a cool bag that failed. Wrote it up.

Cool bag, thermometer, thirteen hours. It held at the right temperature the whole way and I have written down exactly which bag and exactly how much ice.

Security did not blink. Six airports now and not one of them has asked me a single question, and I still carry the letter.

Forty degrees tomorrow.