BOS Gradient Filter element is the first of its kind, with seamless design and true gradient density. This absolute rated element provides users with the depth of a cartridge and the convenience of a bag. This 100% polypropylene microfiber product adsorbs up to 16 times its own weight in hydrocarbons (oils) and will last up to 18 times the life of other products (depending on particle distribution and application). Seadon's BOSG filter bag is independently developed and is a direct replacement to FSI BOS gradient filter bags.