I have used a Tamrac 787 for the past twelve years. It easily accommodates two Hasselblad bodies/backs and three or more lenses plus other goodies and a Gortex shell and many rolls of film. The interior can be configured as you wish with removable inserts. It is adjustable for a comfortable fit. Of course it doesn't have to be filled but I prefer more space as opposed to less. There are accessory attachments that can be added as well. My 250 easily fits and it can be configured to fit my 350. It fits overhead compartments in airplanes being just under 20in. I'm not sure what the current model number is and even back the it was costly but it definitely has been worth it.

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