With Molchanovs pulling system it's easy to adjust the rope length: a single finger suffices for increasing the depth, and you can pull up the weights much easier and quicker, and without a worry that they may slip back into the depths. No need to worry about the knots - pulling system holds the rope firmly until you release it. This small device will make your deep diving trainings even more enjoyable.
After you try it, you will never want to go back to handle ropes any other way. Molchanovs pulling system is very valuable to freediving instructors.