There are always colder temps to be found, even during Summer. Don't hesitate a bit to go higher when you've got a lightweight, warm Arrow Rock in your pack. Flex™ technology throughout gives an unparalleled night's rest. 600-fill goose down sleeps well on Whitney or Longs and tuck stitching guards seams against an early demise due to abrasion. A draft tube and ergonomic hood seal out the cold, while a full-length Snag Free zipper allows you to adjust to temperature fluctuations.