Perfluorinated chemicals cover dry-treated climbing ropes for obvious benefits--water- and abrasion-resistance--however they have a ridiculously slow corrosion time meaning that they'll last a longer than any climber's lifetime. This is problematic when ropes rub their treatments off rocky edges when you're lowering off the climb. It adds grease to the rock and more importantly our collective carbon footprint as climbers and humans. Edelrid solved this issue with the Swift Eco Dry Climbing featuring the first eco-friendly dry treatment in existence. It doesn't use any of the aforementioned PFC's and it still meets UI's standards for eliminated water absorption. The Swift's super skinny 8. 9mm is certified as a single half and twin rope which makes it very versatile for multi-pitch climbing but should only be handled by experienced climbers and belayers.