I use a large mason jar, hose and my mouth to pull vac. The first few times pumping, my testicales got large and heavy (which I liked) but my sack was the same, just hung lower cause of the heavy balls. I kept at it and now my sack is getting tennis ball size (maybe) and stays plump for quite some time. Before, I could escape the 4" mason jar mouth w/ease cause my testicales would slip out one by one. Now, however I'm having a slow go at getting out cause my tennis ball size sack. I once only pumped my dick, but now I really enjoy the weight and feel of a full package pump....ill be looking into better equipment soon.