# Cosmic Down 20 Sleeping Bag vs Disco Men's Endless Promise Down Sleeping Bag 15F: specs and price compared

A sourced, side-by-side comparison of the Cosmic Down 20 Sleeping Bag (Kelty) and Disco Men's Endless Promise Down Sleeping Bag 15F (NEMO Equipment) among sleeping bags. Cosmic Down 20 Sleeping Bag is the cheaper of the two at $189.95.

## Side by side

| Spec | Cosmic Down 20 Sleeping Bag | Disco Men's Endless Promise Down Sleeping Bag 15F |
| --- | --- | --- |
| US price | $189.95 | $299.95 |
| Brand | Kelty | NEMO Equipment |
| Released | 2024 | 2024 |
| Temperature rating f | 20 | 15 |
| Insulation type | down | down |
| Fill power | 550 | 650 |
| Shape | semi-rectangular | spoon |
| Packed weight (lb) | 2.44 | 2.69 |
| Packed size | 8 x 13 in | 11.5 x 8.5 in |
| Zipper side | right | left |
| Product note | 550-fill DriDown; ISO comfort 31F, lower limit 21F; regular weight 2 lb 7 oz | Classic Spoon shape (mummy variant with extra shoulder/hip width); 650 FP PFAS-free hydrophobic RDS-certified down; Thermo Gill vents |

## Key differences

- Temperature rating f: Cosmic Down 20 Sleeping Bag 20 vs Disco Men's Endless Promise Down Sleeping Bag 15F 15
- Fill power: Cosmic Down 20 Sleeping Bag 550 vs Disco Men's Endless Promise Down Sleeping Bag 15F 650
- Shape: Cosmic Down 20 Sleeping Bag semi-rectangular vs Disco Men's Endless Promise Down Sleeping Bag 15F spoon
- Packed weight (lb): Cosmic Down 20 Sleeping Bag 2.44 vs Disco Men's Endless Promise Down Sleeping Bag 15F 2.69
- Packed size: Cosmic Down 20 Sleeping Bag 8 x 13 in vs Disco Men's Endless Promise Down Sleeping Bag 15F 11.5 x 8.5 in
- Zipper side: Cosmic Down 20 Sleeping Bag right vs Disco Men's Endless Promise Down Sleeping Bag 15F left
- Product note: Cosmic Down 20 Sleeping Bag 550-fill DriDown; ISO comfort 31F, lower limit 21F; regular weight 2 lb 7 oz vs Disco Men's Endless Promise Down Sleeping Bag 15F Classic Spoon shape (mummy variant with extra shoulder/hip width); 650 FP PFAS-free hydrophobic RDS-certified down; Thermo Gill vents

## What reviewers say

**Cosmic Down 20 Sleeping Bag** — Two whitelisted hands-on testers (CleverHiker, Switchback Travel) reviewed the Kelty Cosmic Down 20 and both call it a strong-value budget 3-season down bag. Both praise its warmth-to-weight ratio, buttery-soft lining, and low price, and both flag it as heavy and bulky for a backpacking-specific bag while noting the large gap between the women's and unisex versions. CleverHiker's tester observed comfortable warmth to 30F against the 20F spec. All six quotes and the one measured value were verified as literal substrings of the fetched source text. (2 sourced reviews.)

## Sources

- Cosmic Down 20 Sleeping Bag: https://kelty.com/products/cosmic-down-20 (kelty.com, verified 2026-06-20)
- Disco Men's Endless Promise Down Sleeping Bag 15F: https://www.nemoequipment.com/products/disco-mens-endless-promise-down-sleeping-bag (nemoequipment.com, verified 2026-06-20)

Canonical: https://frontdeskreview.com/gear/sleeping-bags/kelty-cosmic-down-20-vs-nemo-disco-15-endless-promise/
Cite: Per The Front Desk Review, Cosmic Down 20 Sleeping Bag ($189.95) vs Disco Men's Endless Promise Down Sleeping Bag 15F ($299.95) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/sleeping-bags/kelty-cosmic-down-20-vs-nemo-disco-15-endless-promise/
License: CC BY 4.0.