Just returned from 10 day trip to Yellowstone National Park and Grand Teton National park.hiked over 12 miles of trails with this back pack containing 2 Digital SLRS,a 70-200,300 prime,a 1.4 converter a 17-85.also contained a flash unit battery chargers and spare compact flash cards.we were caught in rain during the hike but the zipper system on this pack has rain flaps with zip string to keep water from entering this pack.another fine feature is the tripod pocket and starps to secure it to the pack when not in use.the padding on the harness system is very thick and is very comfortable.would buy this product several times over.