The Presta valve has an internal human body, a valve cap, and an outer stem. What's more, it features a lock nut which makes use of to protected the stem on the wheel rim. The air pumping process of this valve is a bit tricky due to small valve diameter. https://bookmarkshut.com/story21031002/how-much-you-need-to-expect-you-ll-pay-for-a-good-presta-addons