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So you’ve just spent £140 on the all new Arc’teryx Lithos SL climbing harness, you slide it out of its premium quality, black, roll-top storage sack and you could be forgiven for wondering what you’ve actually received for all that money. But in the backstory to the Lithos – that is exactly the point.
Refined is the word that first comes to mind. This thing looks refined, it feels refined and it’s actually, incredibly refined. Refined as in stripped down, refined as in optimised, refined as in high class fashion design.
There’s no beefy padding, there’s no huge logos, you don’t get tonnes of gear loops. It’s stripped down to exactly what is needed, keeping in mind the intended end user – the sport climber, pushing their level.
Arc’teryx say:
“The Lithos SL Harness is Arc’teryx’s pinnacle sport-climbing harness, engineered for redpoint attempts, competition climbing, and high-end performance. Developed in collaboration with elite climbers like Alannah Yip and Jonathan Siegrist, the Lithos SL sets a new standard for harness durability and sizing under a new structural platform.”
I think there is often an expectation within gear design and innovation to be adding cool features and reinventing the wheel. But I’d say as a consumer, keen climber and professional mountain guide, I’m generally looking for simplicity and optimisation. Only the features I need, none of the bells and whistles and superfluous extra stuff. Simple works, there’s less to go wrong, less to wear out and less to get in the way.
For a sport climbing harness I want something that I barely notice when I’m climbing but that is like a comfy chair when I’m hanging in it. It needs to carry at least 20 quickdraws and I also want it to last a long time. So I’m actually asking for a lot out of something that I want to also be not much.
A complication that I’ve always found when sizing a harness for rock climbing is that if I choose my correct waist size, the leg loops are too tight. I have a relatively small “rock climber’s” waist compared to my “alpinist’s” legs. So if I buy a small harness it fits my waist perfectly but the legs are tight and restrictive. So why not just buy a harness with adjustable leg loops I hear you ask? Well as I said earlier, I want simplicity and optimisation, not necessarily additional features.
So one of the key things and the main headline for the release of this new Arc’teryx Lithos SL Harness, is a new sizing system. It offers 6 waist sizes. BUT for each one, you have a choice of 2 leg loop sizes. BOOM! Innovation does not need to be complicated. It’s an idea so simple, we’ve probably all thought of it before. But now Arc’teryx have brought it to life. And I have a harness that fits my waist and leg size perfectly. Tailoring for rock climbing harnesses!
I have a 30inch waist and I wanted the larger leg loops so I chose size 2B and this has been great for me.
One final thing to add here is that the new sizing system is Unisex.
Arc’teryx say:
“The Lithos SL features a new industry-first sizing system that replaces gender-specific fits with six waist sizes and two leg loop options per size, providing more freedom of choice across a range of body shapes and allowing climbers to dial in a truly personalized fit.”
So what else do we get for our money I hear you ask?
Anyone who’s been familiar with Arc’teryx’s climbing harnesses in the past will know their “Warp Strength Technology”. For the Lithos SL they’ve optimised this further.
Arc’teryx say:
“Featuring the next evolution of Warp Strength Technology™, Warp 2.0 builds upon the principles of warp strength to deliver a thinner, lighter, and more durable load bearing structure. The swami and leg loops integrate structural fabric for unmatched support and comfort in a minimal waistbelt that is less than 2mm thick at the center back, which features high-tenacity webbing that minimizes stretching from moisture. Paired with a forged buckle, elements are engineered to work together to improve cinching, prevent buckle creep, and enable an easier on-and-off experience for the wearer.”
“Leg loops are developed with a blend of nylon and UHMWPE fibers to create a highly durable webbing composite that is 6mm thinner without sacrificing strength. Designed in a continuous leg loop style to eliminate hard points, improve mobility and durability.”
Despite having zero padding, I’ve always found Arc’teryx harnesses to be remarkably comfortable and the Lithos SL is no exception. The system is super supportive, spreads the load, holds its shape and is comfortable against the skin.
Other key features include 2 snap-fit molded gear loops which feel solid and secure, are well positioned and hold 20 quickdraws easily (euro sport pitches can be long!)
The belay loop is constructed from high strength spun fibers encased in a protective sheath. This design delivers more than double the strength of previous Arc’teryx belay loops, while improving flexibility and eliminating hardpoints caused by structural stitching. This kind of thing isn’t a new concept with brands like Blue Ice having used it on their harnesses for a while, but it is something which should become an industry standard in my opinion.
The Lithos SL is not the lightest harness on the market at 275g for a size 4A. However it is pretty light and blends this with superb quality, durability, support and freedom of movement.
Having used it solely for sport climbing over the last few months I can safely say that this harness is durable. It’s also comfortable. Other than that, I don’t really notice it that much. Which is praise indeed, as thats exactly what I’m looking for in a sport climbing harness.
Overall, the Lithos SL feels like a premium specialist tool rather than an all rounder. And that’s because it is! If your climbing revolves around steep limestone, gym sessions, redpoint burns, and traveling light, then I’d say it’s one of the most refined sport harnesses currently available.
RRP: £140/€150
You can find out more about the Lithos SL and buy one from the Arc’teryx website
Climbing Gear Reviews 