Anatomy of the Penis
Penis enlargement products enhance the body's natural blood flow to the erectile chambers of the penis. The increased amount of blood flow during arousal causes your erectile chambers to expand, producing a larger and thicker feeling erection.
Your penis size is determined by the amount of blood you hold in your erectile tissue chambers (corpora cavernosa). Those are the chambers located inside of your penis that hold blood during an erection. The various enlargement methods all target those chambers, increasing blood flow to them and expanding their size in general.
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