The Bestway Air Hammer™ 850 ML Manual Air Pump inflates tubes, air mattresses, rafts, toys and other inflatables. Designed to provide maximum airflow, this pump has a stroke volume of 0.85 L/cycle and features a large air chamber for rapid inflation. It delivers a continuous stream of air on both the up and down strokes, meaning you're able to fill your items faster than single-action pumps. It's great if you don't have access to electricity and times where you need to inflate your items on-the-go. Plus, three universal valve adapters are included to fit nearly every inflation valve, so you're able to inflate a variety of items with the same Bestway Air Hammer pump!