In the world of climbing gear, breakthroughs in technology often come at a glacial pace. However, sometimes a radical innovation bursts onto the scene—like Aluula's newly developed “Graflyte” fabric, which could redefine what's possible in high-altitude climbing equipment. This revolutionary material, known for its strikingly white appearance, promises to be alpinism's next big ticket item.

What is Graflyte?

Graflyte is an ultra-light, durable, and waterproof fabric made from ultra-high-molecular-weight polyethylene (UHMWPE), better recognized by the brand name Dyneema. What sets Graflyte apart is its unique ability to be laminated together, eliminating traditional failure-prone seams and glue, which typically shorten the lifespan of climbing packs. This advanced fabric forms the backbone of Arc'teryx's latest alpine marvel, the Alpha SL. Weighing in at a mere 438 grams (15.2 ounces) for the 30-liter version, this pack is a lean and mean climbing machine.

Testing in the Wild

Our team at Climbing Magazine was fortunate enough to test the 30-liter Alpha SL pack in several breathtaking locations, from the granite spires of Squamish, B.C., to the rugged terrain of Colorado, and finally amidst the striking beauty of the Bugaboos in Canada. Across these varied conditions, testers praised the Alpha SL for its minimalist design, lightweight feel, and practical features that cater perfectly to the alpinist's needs.

Decoding Graflyte's Functionality

The miracle of Graflyte lies not only in its remarkable strength-to-weight ratio—up to eight times stronger than steel—but also in its construction methods. Thanks to the self-adhering properties of Aluula's fabric, the Alpha SL features a mix of lamination and traditional stitching, where necessary. According to Ryan Hetzel, a designer at Arc'teryx, the aim is to gradually reduce the stitching as designers master working with Graflyte.

How It Performs

When it comes to carrying gear, the Alpha SL handles the load adeptly, albeit with some caveats. Its unpadded, 4mm hip belt doesn't scream comfort, but it effectively distributes weight during long hikes. The back panel offers adequate support, while shoulder straps strike a good balance between cushioning and mobility. However, testers felt that load lifter straps would make a significant difference when the pack is fully loaded, especially on demanding ascents.

Alpha SL vs. Alpha FL: What Sets Them Apart?

While the Alpha SL and its predecessor, the Alpha FL, share a similar sleek design, they are distinctly different in key aspects. The SL is significantly lighter and features a tapered design that enhances hip mobility, crucial for alpine climbing maneuvers. However, its closure system—a triangular flap—does not offer the same weatherproofing as the FL’s classic roll-top design, potentially compromising gear protection in wet conditions.

Looking Ahead: Availability and Future Models

Set to hit the market in spring 2025, the Alpha SL's initial launch will focus on the 30-liter size, with hopes that larger models will follow to accommodate overnight alpine expeditions. Our team will continue testing this pack in various conditions, with updates on its durability and performance following winter adventures in Patagonia and the Canadian Rockies.

Pros of the Alpha SL:

- Feather-light construction - Durable and weather-resistant - Versatile strap system - Easy access internal pocket for gear - Comfortable weight distribution - Secure buckle for ice-straps, even while wearing gloves - Bright interior for easy visibility

Cons to Consider:

- Limited padding on hip belt - Needs more load lifter straps for comfort during heavy loads - Less weatherproof than its FL counterpart

As the excitement builds for this innovative pack, one thing is clear: the Alpha SL is set to disrupt the climbing gear market with its extraordinary blend of lightweight performance and advanced materials! Stay tuned as we explore its long-term performance on our alpine adventures!