Earth Start 20 Gallon 5 Bubble Bag Herbal Oil Extraction Kit with Pressing Screen Composed of high grade double stiched canvas Help remove dust and contamination Bags are color coded by microscreen sizes, Blue: 220 Microns, Red: 160 Microns, Light Green: 120 Microns, Yellow: 73 Microns, Purple: 25 Microns Each bag features built in draw string to easily attach to filtering bucket Includes Pressing Screen