Side sleepers may need more shoulder, hip and knee room than a narrow mummy bag provides.
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How to use this answer
Check girths and try the bag while turned on your side. This separates a useful measurement from a broad product label and helps identify which exact variant needs further checking.
Decision boundary
The listed values describe a product under its stated source conditions. They do not establish personal comfort, safety, stock, or fit in every shelter.
Temperature and fit context
ISO 23537-1:2022 describes adult bag testing under controlled conditions. Product labels and untested claims are not interchangeable with comfort or lower-limit numbers. A sleeping pad, clothing, humidity and individual metabolism change real comfort.
For this question, check: ISO comfort and lower limit where available, maximum user height, shoulder room, fill and actual pad insulation. When a particular specification is absent, keep the decision open rather than treating a missing value as zero or assuming a universal fit.
Compare actual recorded values
The values below come from exact catalog variants. The table is an illustration of which measurements to compare, not a ranking or a recommendation. Open each card for the field source and revision notes.
| Exact variant | Listed fit height | Shoulder girth | Listed weight |
|---|---|---|---|
| REI Co-op Magma 15 — Short Wide | 65.0 in (165 cm) | 69.0 in (175 cm) | 2.27 lb (1,032 g) |
| EXPED Terra 15 — Medium Wide / Left Zip | 72.0 in (183 cm) | 67.0 in (170 cm) | 3.03 lb (1,375 g) |
| Sea to Summit Circuit Down Sleeping Bag — 30F / Regular Wide | 72.8 in (185 cm) | Not verified | 1.96 lb (890 g) |
These records illustrate how the reported measurements and source links are presented; they are not personal field tests or ranked recommendations.
Search an example model on Amazon
This is one source-documented example from the comparison above, not a personal field-test recommendation. Verify the exact model and size on Amazon before ordering.
Search for REI Co-op Magma 15 and check the exact size, revision and seller details before ordering.
(paid link)Search this model on AmazonAmazon search results may include different variants or sellers. No price or stock is verified here.Before you rely on a number
Recheck manufacturer instructions and the exact year, size and SKU. The October 30, 2026 dataset does not verify real-time inventory, sale prices, field performance or a guaranteed safe temperature. If the key measurement for this question is unavailable, ask the maker or measure your own equipment before committing to a setup.
Sources and further reading
Source pages and product listings can change. Specifications were assembled from the supplied dataset as of October 30, 2026; current availability is not guaranteed.
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