Osprey Ultralight Stuff Backpack vs Osprey Siskin 8 Hydration Backpack

The main difference between the Osprey Ultralight Stuff Backpack and the Osprey Siskin 8 Hydration Backpack is that the Ultralight Stuff Backpack has Side Pockets (Side pockets can fit water bottle ) while the Siskin 8 Hydration Backpack does not.

Osprey Ultralight Stuff Backpack Front View
Osprey Siskin 8 Hydration Backpack Front View
Specs Brand Osprey Osprey
Name Ultralight Stuff Backpack Siskin 8 Hydration Backpack
Category Hiking Hydration
Sub Category Daypack Outdoor
Capacity (L) 18L 8L
Dimensions (in) 17 x 9 x 7 18.5 x 8.5 x 6.9
Weight (lb) 0.2 1.2
Fabric 40D Nylon Ripstop 900x600D Polyester
Color 4 colors and patterns 3 colors and patterns
Warranty Osprey Lifetime Warranty Osprey Lifetime Warranty
Release Date May 30, 2015 December 5, 2018
Rating 4.6 4.8
Price Under $50 Under $100
General Features Shoulder Straps Breathable mesh shoulder straps Adjustable shoulder straps
Sternum / Chest Straps Adjustable sternum strap with magnetic valve
Main Compartment Access Normal zipped access Full front zipped access
External Pockets 1 zipped top pocket and 2 side pockets Top zipped pocket
Internal Compartments Internal scratch-free slash pocket
Side Pockets Side pockets can fit water bottle
Water Bottle Yes No
Handles Top grab handle Top grab handle
Loops and Attachments LidLock helmet attachment, ;oop for blinky light attachment
Travel Features Packable / Foldable Folds into its built-in storage pocket
Compression Straps External compression straps
Hiking / Backpacking Features Back Panel Mesh-covered extra deep ridged foam with center air channel
Reflective Safety Strips Reflective accent
Hydration Features Bladder Size Includes Osprey Hydraulics LT 2.5L reservoir by Hydrapak
Hydration Compatible Yes

You're currently comparing the Ultralight Stuff Backpack by Osprey against the Siskin 8 Hydration Backpack by Osprey .


Osprey 's Ultralight Stuff Backpack is a Hiking backpack with Daypack features while Osprey 's Siskin 8 Hydration Backpack is a Hydration backpack with Outdoor features.

The Osprey Ultralight Stuff Backpack has a capacity of 18L (liters), weighs 0.2 pounds and it's dimensions in inches are 17 x 9 x 7. It's made of 40D Nylon Ripstop and is available in 4 colors and patterns in comparison the Osprey Siskin 8 Hydration Backpack's capacity is 8L with a size of 18.5 x 8.5 x 6.9 inches. Constructed from 900x600D Polyester it weighs 1.2 pounds and is available in 3 colors and patterns.