If you're looking for a piece of equipment to complement your gym, this is the perfect fit.
The number of exercises you can do is almost unlimited with this set of pulleys, and it takes up almost zero space: pull-ups for your back, triceps pulley, hamstrings, biceps curl ... all on one setup!
It sounds too good to be true, but you can get a full body workout with this set of pulleys.
This is perhaps the simplest and most effective addition you can make to your gym.