Sierra Designs Boswell 20° Degree Synthetic Sleeping Bag - Blue/Grey

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Make camping easier and more enjoyable with gear designed to give you the best outdoor experience. The Boswell Sleeping Bag is packed with convenient and comfortable features at a value price for beginner campers or experts of leisure. Its oversized shape provides a roomy fit, meaning side and stomach sleepers can shift positions comfortably throughout the night. Soft pongee fabric at the neck transitions to SierraLoft™ synthetic insulation for all-over warmth the second you crawl into bed, and the shell’s durable water repellent (DWR) coating ensures damp nights don’t ruin a deep sleep. Plus, intuitive details like a dual-sliding, anti-snag zipper, adjustable hood and internal stash pocket prevent midnight discomforts so you can be more refreshed for the next day’s outdoor discoveries.


  • Recycled 68 denier polyester shell and 75 denier soft pongee lining for a lightweight, durable bag with reduced environmental impact.
  • Soft pongee neck fabric adds extra comfort.
  • C0 DWR with no PFCs.
  • SierraLoft™ synthetic insulation is designed to capture warm air and keep it close to your body.
  • Oversized fit allows you to stretch and move for a good night's sleep.
  • The dual-zip closure allows you to open the bag in different ways for better ventilation.
  • The drawstring hood traps heat.
  • Internal storage pocket offers convenient storage.
  • Anti-snag zippers for easy use with draft tube along the zipper to keep heat from escaping.
  • Easy-roll straps attached to the bottom of the bag for compact storage.


  • Exterior: 68D partially recycled polyester
  • Lining: 68D partially recycled polyester pongee


  • Low temperature rating: 20.0° F / -7.0° C
  • Bag Shape: Rectangular with hood
  • Weight: 5 lbs 5.4 oz / 2.42 kg
  • Filling Weight: 64.2 oz / 1.82 kg
  • Fits: 78.0" / 198.0 cm
  • Length: 84.0" / 213.0 cm
  • Shoulder circumference: 68.0" / 173.0 cm
  • Hip circumference: 68.0" / 173.0 cm
  • Foot circumference: 68.0" / 173.0 cm
  • Storage bag size: 11 x 15" / 28 x 38 cm


Delivery Details

In-stock items are dispatched the same day if ordered before 2pm (Monday - Friday) or the next working day if ordered after 2pm or on a weekend.

Deliveries are normally next working day for orders over £60. If under £60, we sometimes use a 48 hour service. You will have the option to upgrade to a next day service at the checkout.

Special Order items are dispatched within the timescales displayed after selecting your size.

Most orders are dispatched using DPD Next Working Day.

We use Royal Mail 24 for the more remote parts of Scotland, the Channel Islands and Northern Ireland. Please allow a little extra time for delivery in these areas.

For orders under £60, we normally dispatch using Royal Mail 48 with delivery being made in 2 to 3 days. You will have the option to upgrade to a next day service in the checkout.

A tracking number will be emailed to you for all orders over £60 on the day of dispatch.

For orders under £60 dispatched using an untracked economy service, a reference number will be emailed, but you will not get full tracking, only confirmation once delivery has been attempted.

Other Questions

Sometimes you will see 'Special Order' when selecting your size. For these items, we will dispatch once we have received them from our supplier.

An estimated lead time will be displayed for Special Order items.

Yes, returns are accepted within 30 days of purchase so long as it is unused and still in it's original packaging*.

You can return for an exchange or refund.

Refunds are carried out immediately after receiving your item back. Return postage is at your own cost.

* for safety reasons, we do not accept the return of climbing equipment or underwear once it has been tried on.

All items sold come with a minimum 12 month warranty that covers defects in materials or workmanship.

Certain brands offer an additional warranty. You can find this information on the brands own website, or you can contact us for additional information.

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