5 piece set to meet your various needs. Precautions for Use: Tighten the air valve. If you drive loose, it may come off due to vibration during driving. After installation, make sure there is no loosen or fall off regularly. Be careful when tightened at an angle, the screws will break and damage the valve itself. If the seal is too tight, the valve may be damaged or difficult to remove. Do not use for anything other than the intended purpose. We do not provide support for installation, if you do not know how to install, please consult your local bicycle repair shop. Product specifications and appearance may change without prior notice due to product improvements. There may be some scratches or stains. Thanks for your understanding.