MOUNTAINTOP 50+5 Liter Internal Frame Backpack Rain Cover -EXPANDABLE COLLAR- An extension collar with drawstring on the top can expand the pack and increase the main compartment capacity by 5 liters. -BIG FRONT POCKET- Zippered front pocket comes way down to the bottom. -6 COMPRESSION STRAPS- For tying up your pack or hanging sleeping bag, tent, hammock, and other gears. Elastic bands on them can keep the extra strap from dangling all around the pack. -HYDRATION SYSTEM COMPATIBLE- Hydration access on a side of the pack with water bladder sleeve in the main compartment. -WARRANTY- Includes 90 days limited manufacturers warranty