That's awesome you are going on a safari! As far as duffel size, one question to consider is density of what you are packing. If you are packing denser, heavier items, you can scale down on the size of the duffel. If you are primarily packing clothing and want to have a bit of space flexibility, I would recommend the Big Haul 60. It is only 3 oz heavier than the Big Haul 40, but has quite a bit more space. One great thing about this duffel is that it has compression straps on the sides, so you can cinch down your load if you have extra space in the bag. This also makes packing and unpacking a little easier, since you don't feel like you have to stuff everything in.
Hope you have a great trip!
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