My husband travels frequently on very long flights and I do occasionally. He is concerned as several colleagues have had blood clots after long flights. We both are taking long flights this month and thought purchasing compression socks might be prudent. We are late 50's, neither has had history of edema, my husband takes ambien on flights. Any recommendations? he is 6'2' and I am 5'4'. Thank you very much! Just choosing online is way too confusing.