Comes in two sizes to fit most packs. Medium fits packs 40-60 litres in volume. Large fits packs 60-75 litres in volume.FeaturesPacks into itselfIncludes draw cord to adjust fitZips closed to protect pack when checkedWorks with pack straps for rain protectionBUILD YOUR OWN PACKING SYSTEMPart of a coordinated system for optimized packing. Customize your experience by adding on smart packing and organization accessories that meet your exact needs.OSPREY ACCESSORIES INNOVATIONAll of our accessories have been overhauled to offer better organization, operation, comfort and reduced environmental impact.SUSTAINABLE DESIGN+ bluesign® approved main body fabrics+ GRS-certified 100% recycled main body fabrics+ All DWR treatments made without PFAS