Synthesis 35 Sleeping Bag

Sierra Designs
Sold and shipped by Twist Distribution Ltd
Option: Blue
Choose a Size
View Size Guide
Whether you're road tripping or backpacking, there's never a reason to sacrifice quality sleep over dependable camping gear. Transform your setup with the Synthesis 35, our do-it-all sleeping bag that combines our SierraLoft™ synthetic insulation with lightweight, durable materials that are typically reserved for more premium sleeping bags. Its dual, anti-snag zipper system makes sleepy midnight adjustments easy, and a draft collar along the zipper prevents uncomfortable cold spots from touching your skin. To help you fine-tune your temperature, our patented self-sealing foot vent adds instant ventilation at the toe, while the cinching hood locks in heat at the head (and doubles as a barrier when your pillow likes to run away). Plus, with a durable water repellent (DWR) treatment, a little rain will never ruin your peaceful night. Key features: • Synthetic insulation provides lofty warmth, even when wet • Dual zipper system for ease of use • Patented self-sealing foot vents for fast and easy ventilation • Draft dodger collar helps prevent drafts • 20D nylon fabric for lightweight versatility Materials: • Insulation: SierraLoft™ Synthetic • Shell Fabric: 20d Nylon ripstop • Liner Fabric: 20d Nylon Taffeta Specifications (medium size): • EN Limit Temp Rating: 25F / -4C • EN Comfort Temp Rating: 35F / 1C • Fill Weight: 23oz / 662g • Minimum Weight: 2lb 4oz / 1021g • Fits Up To: 6' 0" / 183 cm • Length: 76in / 193 cm • Shoulder Circumference: 62" / 152 cm • Hip Circumference: 56" / 142 cm • Footbox Circumference: 40" / 102 cm • Mesh Stoarge Bag Size (LxW): 20 x 12" / 51 x 31 cm • Stuff Sack Size (L x W): 15 x 7.5" / 38 x 19cm • SKU: 90613519 Specifications (large size): • EN Limit Temp Rating: 25F / -4C • EN Comfort Temp Rating: 35F / 1C • Fill Weight: 25oz / 720g • Minimum Weight: 2lbs 6oz / 1080g • Fits Up To: 6' 6" / 198 cm • Length: 82in / 208 cm • Shoulder Circumference: 64" / 163 cm • Hip Circumference: 58" / 147 cm • Footbox Circumference: 42" / 107 cm • Mesh Stoarge Bag Size (LxW): 20 x 12" / 51 x 31 cm • Stuff Sack Size (L x W): 15 x 7.5" / 38 x 19cm • SKU: 90613519

Fabric Composition

20d recycled polyester 15%, Sierraloft fill 85%

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UK Deliveries

  • UK Mainland

    • FREE Standard Delivery within 3-5 working days on orders over £75

    • £5.95 Standard Delivery on orders under £75

    • FREE Express Delivery within 1-2 working days on orders over £150 - order before 1pm

    • £5.95 Express Delivery on orders under £150

  • Scottish Highlands, Isle of Man, Isle of Wight & Isles of Scilly

    • FREE Standard Delivery within 3-5 working days on orders over £75

    • £5.95 Standard Delivery on orders under £75

  • Northern Ireland

    • FREE Standard Delivery within 3-5 working days on orders over £75

    • £9 Standard Delivery on orders under £75

  • Orders are sent via FedEx or PDP

UK Return & Refund Policy

  • Orders can be returned within 60 days of receipt

  • The products must be in their original packaging, with all tags and in original condition

  • Returns are free

  • For faulty or damaged items, please contact Mountain warehouse Customer Service team

Return method:

  • To return your order, create your freepost return label at https://returns.sorted.com/exxel/

  • Please safely pack your items in secure, protective packaging to ensure they arrive undamaged.

  • Take your package to your nearest drop off point. To find your nearest drop-off point, visit https://www.yodel.co.uk/store-locator.

  • Please retain proof of postage until it has been confirmed that your refund has been processed.

  • Please note that items sold by Twist Distribution Ltd cannot be returned to Mountain Warehouse stores.

Return address:

For more information or help, please contact Mountain Warehouse's Customer Care.

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