I like this system that I made, because with the doubled sling and the angle of the rope more open (through the block and rings), it allows to have more workload. It is very simple and you can retrieve it from the ground. I showed the easiest way to retrieve, there are other more efficient systems but they're more complicated to prepare. If you use a sling with 2 different sizes rings, one smaller that the other one, keep the bigger one at the outside of the system for a better workload.
