A waist belt positioned below the flotationfoam keeps the vest in place.
有一条腰带在漂浮泡沫下面的位置保持背心在适当的位置。
2
An inflatable PFD has less bulk and interference than a foam unit, but is ready to provide flotation during an unexpected entry into the water.
可膨胀的PFD有较少的体积和没有了干扰泡沫单位，但在想不到的进入水后实时提供漂浮。
3
These substances foam floating on the surface of the water, after the pile of the more, the product is thicker, finally from flotation device to escape into the sewer.