The force you need to apply is just enough to induce micro-tears in your penis tissue. Fortunately, this is way less than 3 lbs. of force. In fact, the micro-tears are safely generated by applying small to moderate force for long periods of time. Applying a small force for long periods of time (4-6 hours a day), is the correct way to create the micro-tears and go about penis stretching. It’s also the best way to ensure safety and prevent injury.
The vacuum pump. This is a cylinder that sucks out air. You stick your penis in and the resulting vacuum draws extra blood into it, making it erect and a little bigger. You then clamp off the penis with a tight ring -- like a tourniquet -- to keep the blood from leaking back into your body. What are the drawbacks? The effect only lasts as long as you have the ring on. Using it for more than 20 to 30 minutes can cause tissue damage. This is sometimes used as a treatment for erectile dysfunction, but has not been proven to actually increase the size of the penis.