For those times when you need to stack lenses in a camera bag, but don't want them banging against each other possibly marring their surfaces, use a Rear Lens Cap Pad. You can make your own by getting an adhesive-back pad, cutting it to the diameter of your rear cap, and applying. (Click on image for an enlarged view.)
I use this technique for packing my Lowepro Fastpack 250. The 70-200mm zoom lens lays horzontally in the camera compartment, then my 50mm sits on top of the barrel with the Cap Pad so as not to scratch it. This method takes up less room than individual lens pouches, and it provides faster access too.
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