A. This bicycle Presta valve extender is designed for road bike tires and can extend the valves of tubular tires and inner tubes. It is made of metal, which is sturdy and durable, effectively meeting daily usage needs. B. This product is available in various specifications. There are non - detachable 45mm and 80mm specifications, as well as detachable 45mm and 80mm specifications. When you purchase 2 pieces of each specification at one time, an installation/removal wrench will be given as a gift to facilitate your installation and removal operations. In addition, there is also a specification with 100 detachable valve seals for you to choose from. C. It is suitable for all genders, including men, women, and the neutral group. This Presta valve extender is not an imported product, nor is it specifically designed for children. D. It can be adapted to various sales platforms and sales regions, and is widely applicable to various bicycle usage scenarios, providing convenience for inflating your bicycle tires.