Check the listing for details. 100 pack Rosin bags 2" x 4.5" 37u MICRON, Rosin Press. Condition: New. Listed at 49.99 USD. You are purchasing Rosin Bags 2" x 4.5 37 micron 10 x 10 packs poly bags, total 100 bags good to 300fInside out stitchingTea Bag Filters are specially designed 90µ micron screens for pressing solventless oil using the Rosin Technique. Use the open side of the filter sleeve to insert your flowers or dry sifted material.Yes the bags or tubes can be reused. You can clean them multiple ways Soak in alcohol, then scrape out old material, soak in alcohol again, then clean with very hot water and soap. Make sure to be very gentle with the seam. Another option is to simmer them in coconut oil rather than soaking the tubes in alcohol.What is the difference with the micron sizes? Is one better than the other?Micron size has a lot to do with personal preference. The 25u offers a smaller hole and gives you a more filtered and refined product whereas the 50u offers larger holes that allow material to pass through easier and can sometimes give you a slightly heavier yields. Lower number for bubble and keif, and larger number for flower is preferred. Mush have for your rosin press, rosin tech, sho, solventless oil, low pressure high heat, low heat high pressure, closed loop extractor,