DP 4000 is an amazing pump. You will be stoked at how quickly you will grow. I used to pump a few years ago and decided to get back into it. Glad I made this move and went with this great pump. Easy to set up on my windows laptop so you'll be pumping in no time at all. The pump and cylinder holds pressure well and is very stimulating to your junk. You'll be huge in no time. Im already ordering the next size up in cylinder and I've only been at it two weeks.