Trilogy Sky 25+ Backpack delivers precision fit and rugged performance for alpine pursuits
What Our Gearhead® Experts Are Saying:
"When you’re climbing high and moving fast, the Trilogy Sky 25+ hits that sweet spot of fit, function, and weight. The Boa® adjustment system is a game-changer—it’s the most secure and dialed-in carry I’ve ever had on technical terrain."
Designed for bold ascents and fast, technical lines, the Millet Trilogy Sky 25+ Backpack is built to move with us across demanding alpine environments. Whether we’re scaling steep ridges, skinning to a couloir, or pushing a summit in variable weather, this pack keeps gear secure and instantly accessible with side zip entry, intuitive pocketing, and a modular setup.
Crafted from incredibly durable Dyneema® fabrics, this alpine pack is abrasion resistant and water repellent, shedding snow and sharp rock with ease. A Boa® LI2 adjustment system delivers a custom-fit harness that stays tight and stable on exposed traverses and vertical scrambles. Dedicated attachments keep our ice tools, rope, and skis in place, while internal hydration compatibility keeps us fueled. Lightweight, technical, and versatile, the Trilogy Sky 25+ is made for mountain athletes who demand total reliability on mission days.
Details
- Technical 25L alpine pack with BOA® harness for precise fit
- Constructed with Dyneema® for lightweight durability and weather resistance
- Side zip access allows gear retrieval even with rope secured on top
- Rope, ice axe, and removable ski carry systems for mountain versatility
- Multiple pockets for efficient gear organization
- Hydration compatible with dedicated sleeve
- Removable gear cord for additional equipment attachment
- Designed in collaboration with mountain professionals for ultimate performance
- Item #MILZ05N
- Material
- [face fabric] 70D Robic nylon, PFC-free DWR finish, [overlays] 300D Dyneema, PFC-free DWR finish, [mesh] Dyneema Stretch (48% nylon, 31% elastane, 21% polyethylene
- Volume
- 25L (1525cu in)
- Shoulder Straps
- harness-style, BOA® adjustable
- Hydration Compatible
- yes
- Reservoir Included
- no
- Access
- side zipper, drawstring top
- Pockets
- 1 front mesh, 1 zippered interior, 2 zippered mesh side, 1 internal hydration compartment
- Gear Loops
- 1 removable equipment cord, removable ski holder, rope holder, FPP ice-axe holder
- Ice Axe Carry
- 2
- Trekking Pole Carry
- 2
- Compression
- side
- Dimensions
- 22.4 x 11.8 x 8.6in
- Claimed Weight
- 1lb 7.2oz
- Activity
- backcountry touring, ice climbing, trad climbing, sport climbing, mountaineering, trail running, hiking
Reviews
Q&A
What do you think about this product?
Overall Rating
5 based on 1 ratings
Review Summary
Fits True To Size
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Selecting an option will reload the available reviews on the pageJune 21, 2025
First of it's Kind
- Familiarity:
- I've used it several times
- Size Bought:
- S/M
- Height:
- 5' 8"
- Weight:
- 150
The Trilogy SKY is SICK! It's the first pack I know of that integrates BOA technology, which allows me to wear the pack without a hip belt and be super comfortable!! I'm really impressed with the durability of it with dyneema as well. Whether I'm scrambling, trail running, ski touring, rock, or alpine climbing, this pack can do it all!!
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