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Climbing Ropes

Mammut Serenity 8.7

Plan A: Get stronger. Plan B: Mammut’s Serenity 8.7mm, the thinnest, lightest UIAA-certified single rope in the universe. The choice was clear.

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 My new route, John Henry, is a meandering peregrination up a scruffy, overlooked crag 20 minutes from the office. The route is cool, but it wanders like your grandma on half a
Quaalude. With the pitch at well over a hundred feet, the rope drag and weight was punking me every time I tried to send the rascal. Plan A: Get stronger. Plan B: Mammut’s Serenity 8.7mm, the thinnest, lightest UIAA-certified single rope in the universe. The choice was clear.

I was a tad skeptical the first time I tied into the skinny 8.7mm lead cord. I questioned the performance and durability. Would my belayer have trouble holding falls? Would I hit the end of the rope like a rock tied to the tip of a bullwhip? And how would the skimpy line hold up to numerous falls? My distrust was quickly allayed, however, and replaced with esteem. Where other ropes tugged on my harness like a Silverback hitching a ride, the Serenity flowed through the circuitous pro like a brook in its banks, and the weight (52 grams per meter; 6.8l pounds for 60m) hardly registered. My belayers had no trouble catching a multitude of falls, both with traditional friction devices and the new Fader’s SUM, an auto-locking belay device designed to be used with smaller- diameter ropes.

I took numerous whippers on the way to eventually redpointing the new line and haven’t noticed any unusual signs of wear on the rope. It’s worth noting, however, that Mammut touts the Serenity as a specialty rope “designed to favor weight-savings over durability … i.e. redpoint attempts or super-light alpine ascents.” If you’re looking for a dog-a-thon workhorse, pick up a heavier, larger-diameter rope. But for those times when you need a little edge, whether in the high mountains or on a particularly nefarious project, check out Mammut’s Serenity. I’d suggest forking over an extra 20 bucks for a 70-meter ($250) halyard and then pimping it to the fullest.

—Jeff Jackson

Field Tested: The World’s Skinnest Single Ropes Go Head-to-Head

This article was published in Rock and Ice issue 227 (July 2015).