My definition of an Uli is very simple. It is first, the engorgement of the shaft, 80-95%, followed by cutting off of the majority of blood flow by some means, then, an added amount of pressure is applied to super engorge the tissues.
The cutting off of blood flow and added pressure can be done by a number of means: Manually, Uli thing, hanger etc.
This is the mechanism of growth of all of the squeeze techniques. There is nothing complicated about it.
Note: Simply do not leave your penis in an circulation deprived state for very long. You can do many Ulis by whatever method, as long as you provide a rest and restore circulation every few minutes. The penis in the flaccid state does not have much blood flow. So, in an engorged state, it will receive enough nutrients and oxygen even if circulation is cut off for a while.
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