Nano IX $285 for 70 m, $325 for 80 m Time was, 9.0 mm was the standard for a double rope, but this ultra-thin line is certif ied for use as a single, as well as a double or twin rope. At just 52 g per metre, it will appeal to alpinists looking for the lightest possible line. They will also appreciate the dry treatment to both the core and the sheath. Sport climbers who need a light redpoint rope need should also consider the Nano IX. Not an all-rounder for top-roping and heavy abrasion applications, but a great choice for experienced climbers who want to shave weight.