- Lightweight aluminum alloy valve stem nut: made from high‑quality aluminum alloy to minimize weight, it reduces impact on wheel balance and helps you achieve better race results. - No-burden design: this valve stem nut adds no extra load, so you won’t feel heavier or restricted when riding fast. - Robust stability kit: includes 2 nuts, 2 sealing rings, and 1 multi‑function wrench. Note: install the sealing ring before tightening the nut. - Prevents loosening: helps reduce loosening on American rims caused by excessive Presta valve play, improves air tightness, and extends tire life. - Practical use scenarios: - Road racing and high‑speed training to maintain wheel balance and reliable seal. - Wheel maintenance on bikes with American rims prone to valve‑play related loosening. - Long rides or endurance events where consistent air retention and tire life are important.