Sediment depth filters are generally spun polypropylene sediment depth filters, which in reality, are gradient density filters in that the outer layers trap larger particles so that the inside layers are more efficient. They are often called “melt blown” or “spun poly” filters. These filters are generally used in reverse osmosis pre-treatment, food and beverage, microelectronics, and many other applications. Made out of 100% pure polypropylene, a spun polypropylene filter is suitable for any potable water application, including high-purity. There are no glues, binders or additives that can cause side effects in water processing applications.