What is the best filter for rosin?

The best filter for rosin depends on what kind of material you’re pressing (flower, hash, or kief) and what your goals are (yield vs. purity). 

Here’s a quick breakdown:

✅ Material Matters:

• Flower: Most people use 90–120 micron bags. 90µm gives cleaner rosin but lower yield; 120µm gives more yield with a bit more plant material.

• Kief/Dry Sift: 25–37 micron bags are ideal, since kief has no plant matter and you want to catch the smallest particles.

• Bubble Hash/Ice Water Hash: 25–73 micron bags are common — 37µm is the sweet spot for high-quality full-melt hash rosin.

  
  

✅ Material of the Bag:

• Nylon monofilament is the gold standard. It’s heat-resistant, durable, has consistent pore size, and minimal stretch.

• Polyester and silk exist, but nylon is superior for rosin pressing because of its strength and ability to withstand high pressure/temperature.

• Avoid stainless steel mesh bags unless you need extreme durability; they can compromise yield/purity.

  
  

✅ Construction:

• Seamless/welded bags are better than sewn bags because they reduce blowouts and leaks, especially at high pressure.

TL;DR: For most people pressing flower, 90µm nylon monofilament bags with welded seams are the best all-around choice.