1. Measure the erect length of your penis
In order to measure yourself correctly your penis must be in an erect state. This will provide the most accurate method of ensuring you choose the correct pump.
Measure your erect penis with a ruler pressed lightly onto your pubic bone. You`ll find a ruler is easier than a tape measure.
Record the measurement from the pubic bone right up to the tip of your penis.
You will then be able to select a pump from the four ranges provided.