Medium mushroom grow bag. 8" X 4.8" X 19" makes these perfect for spawning grains or growing on bulk substrate. These bags are autoclavable and used for spawn incubation and substrate fruiting. Our medium mushroom grow bags have a microporus filter patch that allows proper gas exchange but will not allow contaminants into the grow bag. Medium mushroom grow bags bags use a .05 micron filter patch so you can seal the bags before sterilization. You can also fruit directly in the bag. This side-gusseted bag gives a sturdy stand-up bag after filling and a strong bottom seal. Our bags are pliable at any temperature as well as after sterilization. The bag opening is designed for easy sealing and the bag"s bottom seal can withstand agitation.