Outdoor Vitals
Outdoor Vitals CS40 Ultra
The CS40 Ultra pairs Challenge UltraWeave 200 with carbon fibre stays for 28.6 oz at 53 L. Outdoor Vitals sells direct, which is why the price sits below comparable cottage packs using the same fabric.
Specifications
Features
Pros
- ✓Carbon fibre stays are stiffer per gram than aluminium, giving good load transfer at low weight.
- ✓Challenge UltraWeave 200 is waterproof and highly tear-resistant.
- ✓$330 undercuts the Bonfus Framus and Zpacks Arc Haul Ultra using comparable fabric.
- ✓53 L is enough for a bear canister and multi-day food.
- ✓Direct-to-consumer sales mean shorter lead times than most cottage brands.
- ✓28.6 oz is competitive with framed packs 5 L smaller.
- ✓EVA foam pad backs the stays for comfort under load.
- ✓Hipbelt pockets included.
Cons
- ✗No published maximum load figure.
- ✗Carbon stays can snap rather than bend if badly overloaded, unlike aluminium.
- ✗UltraWeave is hard to field-repair.
- ✗$330 is still a lot next to the Durston Kakwa 55 at $279.
- ✗No adjustable torso.
- ✗Outdoor Vitals has a shorter track record than the established cottage names.
- ✗Warranty terms are not published the way major brands publish them.
- ✗Limited retail presence for in-person fitting.
Compare the Outdoor Vitals CS40 Ultra
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