100lbs of pasteurized manure based mushroom substrate. You will receive 20 x 5lb bags of substrate. This substrate is fully hydrated, pasteurized and comes in mushroom grow bags with a 5 micron filter patch. The more you buy, the more you save! Enjoy an even deeper discount for Manure Based Mushroom Substrate. Ready to use at your front door! This item can only ship with UPS. Sorry this product is too heavy to offer free shipping on.