Vacuum pumps, also called vacuum erection devices are products that have been developed to treat erectile dysfunction. They consist of a cylinder and pump mechanism (some are battery operated, others are manually operated) , and work by creating a vacuum in the cylinder which in turn draws blood into the penis causing an erection. Vacuum pumps come with constriction rings, which are tight bands of rubber that go around the penis. Essentially the pump gives a man an erection, and the rings keep the blood in the penis, maintaining an erection while they are worn.
Vacuum pumps are essentially the same thing as the more commonly known penis pumps which can be found in sex shops. However only vacuum pumps that are manufactured by medical device manufacturers have been clinically tested, and they tend to be of far better quality and safer, as some regular penis pumps do not come with a release valve to reduce the risks of harm during use.
If you are interested in knowing more about vacuum pumps you can speak with your doctor who will either provide you with information or may refer you to an urologist. Vacuum pumps often require a prescription, and are sold at pharmacies. They are expensive, but if someone has been diagnosed with erectile dysfunction, some insurance plans will cover the cost (or part of the cost) of a vacuum pump.