Black Line Edge When the penis is rigid, the man removes the device from the penis and places an elastic band around the base of the penis so that the blood is trapped keeping the penis erect. The band can be left on the penis for up to half an hour. Some men use the pump at the beginning of the sexual act, while others consider it more convenient to do so when a partial erection has been achieved through pre-sexual intercourse. The erection achieved with the device is usually rigid, but it may pivot at the base of the penis, which can limit comfortable postures in intercourse. It may take some practice to learn how to use the suction device. Most of them are purchased by prescription, but some are available.

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