How strict are airlines about carry on size?

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Tags

1. #allowing
2. #travel
3. #smaller
4. #slightly
5. #airline
6. #varies
7. #commonly
8. #pockets
9. #check
10. #larger
11. #wheels
12. #handles
13. #inches
14. #luggage
15. #including
16. #allowed
17. #carry