Since 1979
Sea to Summit Circuit
For colder nights when extra down insulation is worth the larger packed size. The Circuit combines a roomy semi-tapered rectangular shape with 650+ fill power Ultra-Dry duck down. Open the wraparound zip to vent your feet or lay the bag flat as a quilt.
The semi-tapered rectangular shape gives you room to turn and sleep on your side. A soft brushed lining makes it comfortable against your skin.
The full-length wraparound zip lets you open the footbox for airflow. Unzip completely to use Circuit as a flat quilt on warmer nights.
650+ fill power Ultra-Dry duck down compresses into the supplied sack. This −9°C model packs to 9 L in Short, 9.7 L in Regular or 10.8 L in Long.
Warmth & fit
This −9°C model has a −5°C ISO comfort rating. Start with comfort if you sleep cold and allow a margin for your conditions. Recommended sleeper heights: Short up to 170 cm, Regular up to 185 cm and Long up to 198 cm. Long adds 5 cm of width. The bag lengths below are overall dimensions, not sleeper heights.
| Detail | Short | Regular | Long |
|---|---|---|---|
| Sleeper height | Up to 170 cm | Up to 185 cm | Up to 198 cm |
| Bag weight | 1080 g | 1160 g | 1290 g |
| Packed weight | 1250 g | 1330 g | 1450 g |
| Down fill weight | 664 g | 715 g | 814 g |
| Compressed volume | 9 L | 9.7 L | 10.8 L |
| Bag length × width | 192 × 72.5 cm | 207 × 72.5 cm | 222 × 77.5 cm |
| Packed dimensions | 46 × 27.5 × 18 cm | 46 × 27.5 × 18 cm | 46 × 27.5 × 18 cm |
Specifications
Compare your options
+2°C comfort / −1°C lower limit. Regular 820 g; 5.4 L compressed.
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−5°C comfort / −9°C lower limit. Regular 1160 g; 9.7 L compressed.
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The details to help you choose with confidence.
The model name uses the ISO lower limit: −9°C. Its ISO comfort rating is −5°C. Start with comfort if you sleep cold, and allow a margin for the nights you expect. Ratings are laboratory comparisons, not a guarantee for every sleeper. An insulated mat, shelter and clothing also affect warmth.
Short is recommended for sleepers up to 170 cm, Regular up to 185 cm and Long up to 198 cm. Short and Regular are 72.5 cm wide; Long adds 5 cm of width. These are recommended sleeper heights; 192 cm, 207 cm and 222 cm are the overall bag lengths. Choose a fit that leaves room at your feet without pressing the insulation flat.
Both have the same roomy shape, 650+ fill power down and wraparound zip. The −1°C has a +2°C comfort rating and weighs 820 g in Regular. The −9°C has a −5°C comfort rating and weighs 1160 g in Regular. Choose −9°C for the colder comfort rating, allowing for its greater weight and packed volume.
It opens fully flat as a quilt. You can also open the footbox while keeping the upper section zipped. Circuit bags cannot zip together or couple with other Sea to Summit bags; this model has a left-hand wraparound zip.
No. Ultra-Dry Down and the water-repellent shell help manage moisture, but the bag is not waterproof. Keep it protected from rain and water in your pack and use suitable shelter.
Circuit is a unisex range. Use the comfort rating as your starting point if you sleep cold: −5°C for this model. Choose Short, Regular or Long by your height and the room you need.
The sleeping bag includes a compression sack for transport and a storage cell for keeping it loose between trips. Air it after use, let it dry completely and store it uncompressed. Follow Sea to Summit’s care instructions for cleaning.
Eligible items can be returned within 30 days of purchase, unused with original packaging and labels. Refunds may incur a handling fee; exchanges and store credit avoid it. Return postage is at your cost; conditions apply.
Returns policyContact us before sending anything back, with your order details, photos and a brief description of the issue. We will help with warranty, repair or spare-part options. Coverage varies by product; your consumer rights still apply.
Get warranty helpFor in-stock, standard parcels, standard AU shipping targets 4–6 business days after dispatch and FedEx targets 3–5 business days after dispatch. These are targets, not guarantees. Remote and bulky deliveries can take longer. Preorders, public holidays and carrier delays may affect timing. Contact us if you need an item by a specific date.
Delivery informationStandard AU shipping is $10, or free on eligible orders over $250, excluding heavy or bulky items. FedEx is $25. Product-specific freight charges apply to heavy or bulky items with either service, and remote-area surcharges may apply. Available services and final shipping charges are shown at checkout.
Delivery informationYes, tracking details are sent by email when your order is dispatched. Allow time for the carrier’s first scan. If you cannot find the email, contact us with your order number.
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