How to Choose the Right Cylinder Size (1.75", 2", or 2.125")

The cylinder is the single most important piece of the pump. Get the size wrong and you'll struggle to form a seal, you'll waste effort, and your results will suffer. ## How to measure Measure the circumference (girth) of your erect penis at mid-shaft. That single number tells you everything. ## Sizing chart | Diameter | Best for girths | | --- | --- | | 1.75" | 0" – 5.4" | | 2.00" | 5.5" – 6.25" | | 2.125" | 6.35" – 6.75" | If you're between sizes, go smaller. A snug seal is what you want — the vacuum does the work. ## Outgrowing your cylinder Most men outgrow the 1.75" cylinder within the first 3–4 months. That's a good thing — it means you've gained girth. Upgrade to 2" and keep going. We sell the VulcmanTotal Replacement Cylinder separately so you don't have to buy a whole new kit.