They were originally made by Game Tracker not sure who makes them now, I think Carbon Express. You can usually get them on that we site named aftet a big South American river.

I haven't used the string systems and have seen sections of them while hunting on public land before.

I go home and get my german wirehair. She usually makes short work of it and I have learned to trust her. I get her regardless of whether or not I know exactly where it is so she gets practice and has some fun. Extremely helpful if there is not a lot of blood because I have red-green color deficiency. I keep her on a lead in case animal is still alive.