This must be one of the best value vibrating penis pumps on the market. The smoked cylinder has a smooth rubber seal around the base to ensure that maximum vacuum can be achieved and maintained. Squeeze the bulb to create the desired vacuum, but you can quickly release the vacuum as required by the quick release pressure valve built into the bulb. Turn on the multi speed vibrations at the top of the cylinder for greater stimulation as required. Used daily you can watch your manhood grow the the added benefit of an extra little stimulation. The cylinder measures 9 inches by 2.5 inches.