Handling
The Sterling Fusion Nano IX was a popular rope with testers for its handling owing to its soft, supple feel that took knots with ease. Testers on rock and ice routes appreciated the handling of the rope when making clips and threading the rope through a belay device. When new, it was as popular as any rope tested although after time the rope’s handling got stiff and hence, didn’t score as high as the top handling rope in this group of ropes tested.

Resistance to Dirt
The Fusion Nano got dirty quick compared to other ropes tested. We tested a bright purple version of this rope that when new, offered great appeal to testers and others looking on. Sterling’s dry treatment of the Nano kept dirt at bay during its initial use but after extended use, the sheath got dirty. The dirtiness on the sheath made it difficult to find the middle mark after several days of use and impossible to find after 25 days of use. When before and after pictures were taken the middle mark was impossible to find even in good light.

Durability
The Fusion Nano proved to be the least durable of the ropes tested in this group. While Sterling warns against top-roping or working of routes with the Nano due to its small size, the other skinny ropes tested in this group fared better. During field testing of the Nano, the sheath picked up a lot of wear from overall fuzziness to developing some soft spots in the rope. During our controlled in-house testing the sheath showed more wear in the form of fuzz than any other rope tested. During the sharp edge test the core was exposed more than others and some of the core fibers were severed.

Features
The Fusion Nano is offered in a bicolor pattern, but single color ropes come with a middle mark. The black middle mark on the rope tested was harder to see than other middle marks, likely owing in part to the dark purple color of the rope. On a lighter rope the middle mark would likely be easier to see. However, after several days of use the middle mark wore off quickly compared to other middle marks and after about a dozen days of climbing on rock and ice the middle mark was very difficult to find. By the time I took before and after pictures of the rope the middle mark was impossible to find. All Fusion Nano ropes come dry treated and that treatment proved very effective at warding off moisture and preventing freezing of the rope when ice climbing. The dry treatment performed better than many dry treated ropes although not as well as a couple of select ropes. The Fusion Nano is certified as a single, half and twin rope, offering a variety of options for how you use this rope in varied terrain.

Versatility
Testers found limited versatility in the Fusion Nano and saw it best suited to applications where its light weight and great handling could be leveraged. Testers really liked the Nano for ice and alpine climbing due to its effective dry treatment, good handling, and the ability to use it as a single, half, or twin rope. Sport climbers may find appeal in the rope for a lightweight redpoint rope with easy clipping and handling, but for more extensive work, the durability becomes cause for concern. While trad and multi-pitch climbers looking for a light, easy handling rope may appreciate the Nano, they should be careful due to its durability if they are climbing on sharp, abrasive rock.