The Culligan CP5-BB water filter cartridge is a special formulation of resin-impregnated cellulose and polyester fibers. The Culligan CP5-BB water filter provides higher wet strength than regular cellulose cartridges. The Culligan / Ametek CP5-BB water filters also provide high flow rates and dirt-holding capacity, while maintaining extremely low pressure drop. Nominal 5 micron Culligan CP5-BB Pleated Cellulose Polyester Water Filter Cartridge. 155184 Culligan CP5-BB filter fits in housings for 10 inch Big Blue water filters.