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Big Agnes Lost Dog 15 Sleeping Bag

$199.95 - $219.95

Get lost with the Big Agnes Lost Dog 15 Sleeping Bag. This lightweight, cold weather sleeping system is built with versatility in mind. Whether you need something for car camping adventures where comfort is king, or want to add this to your backpacking kit, the Lost Dog is ready to go with you. The FireLine™ ECO synthetic insulation has a high warmth to weight ratio and is made from 100% recycled polyester material to keep you warm and your conscience clean. A built in Flex Pad Sleeve accommodates pads of multiple widths, allowing you to use this bag with your ultralight sleeping pad or your ultra-comfortable base camp pad. With a rectangular shape that offers plenty of wiggle room from head to toe, the Lost Dog is enough to make you want to head to bed before the sun goes down.


  • Big Agnes system bags combine technical design while maximizing comfort
  • Streamlined silhouette optimizes heat regulation
  • Flex Pad Sleeve stretches to conform to multiple pad sizes
  • Low profile cordlock lets you un-cinch the hood with one hand
  • Regular and long bags fit 20" - 25" wide pads; wide long bags fit 25" - 30" wide pads
  • Free range hood allows you to move your head comfortably
  • Pillow Barn - Keeps your pillow from slipping away during the night
  • Internal hood drawcord gives a secure fit when tightened
  • Free Range Footbox - gives your feet plenty of wiggle room
  • Rectangular shaped bag
  • Anti-snag zipper
  • 65” /152cm YKK #5 anti snag locking zipper - regular bags
  • 70”/165cm YKK #5 anti snag locking zipper - long and wide long bags
  • Zipper Garage
  • Mate together left and right zip bags
  • No-draft collar, No-draft wedge, No-draft zipper
  • Interior fabric loops for sleeping bag liners
  • Exterior loops for hang drying or storage
  • Mesh storage sack & polyester ripstop stuff sack 

Materials and Construction

  • Nylon ripstop shell fabric with a water repellent finish
  • Soft and comfortable polyester lining
  • Flow™ construction increases thermal efficiency
  • FireLine™ ECO Synthetic Insulation - 100% post-consumer recycled polyester


  • Temp Rating: 15° F
  • Bag Size: Regular, Long, or Wide Long
  • Fits Up To: Regular - 5'10"; Long and Wide Long - 6'6"
  • Pad Size: Regular - 20" x 66"; Long - 20" x 72"; Wide Long 25" - 30" x 78"
  • Bag Weight: Regular - 3 lbs 3 oz; Long - 3 lbs 10 oz; Wide Long - 4 lbs
  • Fill Weight: Regular - 31 oz; Long - 35 oz; Wide Long - 40 oz
  • Insulation: FireLine™ ECO synthetic
  • Compressed Size: Regular - 8" x 9.5"; Long - 8" x 10.5"; Wide Long - 9" x 12.5"
  • Stuff Sack Size: Regular and Long - 9" x 20"; Wide Long 10" x 21"