Pack of 5 filter bags 22cm x 13cm Ideal for crystal clear water Made of polyester for optimal filtration and long lifespan Available in 6, 15, and 30 microns for fine filtration Easily installed between two retaining rings Can be cleaned with a water jet or in the washing machine at 30 degrees without detergent Filtration fineness is measured in microns. The smaller the micron rating, the finer the filtration. For reference, a human hair is approximately 50 to 100 microns in diameter. 6-micron filter provides very fine filtration. Suitable for fresh water with low external pollution and for pools with light usage. Retains small impurities to maintain clear, clean water. Requires regular cleaning and maintenance. 15-micron filter is recommended for normal pool use during the swimming season. Provides balanced water conditions and is the most common choice for standard filtration. 30-micron filter is ideal for starting up the pool at the beginning of the season, winterizing, or during extended periods of non-use. Suitable for heavily loaded or unbalanced water, including green or cloudy water. Requires less frequent cleaning compared to finer filters.