The package contains a single shelfMulti-function - Perfectly integrate the bipod with the tactical vertical foregrip into a single unit. Switch from a vertical foregrip to a fully functional Biped at the push of a button.Extensive compatibility - with freely adjustable 20mm retractable guide rail. Easily install and install any 20mm Weaver/picatiny rail system with a side mount to fit a laser light/torch.Easy to use - press the button on the top of the handle to release the bipod legs. Press the button, the legs twitch together and release the button when you feel stuck.Sturdy materials - the air rifle bipod uses internal metallic outer polymer material.< p>Portable - retractable legs reduce space and are easy to carry and use. Only 220 grams in a compact and lightweight package.