BIKING Portable Mini Bicycle Pum P Cycling Hand Air Pum P Ball Tire Inflator Schrader Presta Valve Road Bike AccessoriesThis product description outlines the features and specifications of a portable bicycle pump. Here's a summary of the key points: Product Name : Portable Pump Size : Adjustable from 30x205mm to 30x335mm, indicating it's compact and can extend for use. Using Material : Made from stainless steel and engineering plastics, suggesting durability and lightness. Valve Compatibility : It has a "Reuters Valve" and is compatible with both Schrader and Presta