These bags are 2.2 mil in thickness and offer the same high-quality 1.5” x 1.5” 0.5 micron filter. These are great for standard growth blocks as your test new varieties, or you are just starting out. They are sized to fit 5-7 lbs of substrate. Yes, these Unicorn bags are still the original brand made in the USA to the high-quality standards Unicorn bags are known for. All of our Unicorn bags are Polypropylene which means they are autoclavable. You can even save more time with MushroomMediaOnline’s own Fast Fruiting Mix that is the ideal mix of 50/50 hardwood sawdust substrate supplemented with 50% soy hulls. Free shipping with your bag purchase from MushroomMediaOnline.com We offer the lowest cost per bag by finding the very best shipping rates for your bag delivery. The larger your order size, the more you can save. Choose your purchase size and see the full price with free shipping included. Brand: Unicorn Model Number: 14-A Injection Material: 2.2 Mil Polypropylene Bag Size: 8″ x 5″ x 19 Filter Size: 1.5” x 1.5” 0.5 micron Typical Block Size: 5-7 lbs