What is checked baggage? A checked bag is one that is too large or too heavy to be allowed to be carried onto the plane's passenger cabin. Most smaller aircraft and many international flights require checking your bags for cargo loading. Larger duffels like the Safari-Beanos PR5.5 and PR6, as well as the Expedition Series Sherpa Jr., Big Oxx and Flying Boxcar all are too large for carry-on and have to be checked. Any bag larger then 22x14x9 or 45 inches linear, will have to be checked. To make carrying large heavy bags like our Expediton Series, the Sherpa and Big Oxx both have retractable backpack straps. Observe your airline weight limits on checked bags so there's no delay in getting to your destination on time.