This is one of those products that does just what it says on the tin. I used it to proof a new 60 m,10.2 mm diameter rope. Following the instructions suggested that I should use more than a litre of proofer, but I compensated by soaking the rope in the made up solution for more than the minimum 2 hours. In fact I left it overnight without harm. When it came to the wash stage, I transferred the solution into the machine and used the polyester cycle and a reduced spin speed (800). I then gave it a couple of extra spins at the same speed to initially dry the rope before transferring it to the dryer at low temperature. The instructions recommend that you place your rope in a wash bag so as to avoid tangling it. I found this essential, putting the rope into a large wash net before I started the soaking stage, and keeping it there right through final drying to ease handling. You don't want this stuff splashing on you, and should wear your marigolds when handling the solution. It pongs a bit, but after drying and final airing for a few days it's largely gone. The most obvious first result is that the rope is more pliable and certainly runs better and knots more easily. I have yet to test it's waterproof qualities but, if my prior experience with Nikwax products is anything to go by, It will perform as stated.