This set includes three empty liquid culture jars for growing your own mushrooms. Each jar comes with a lid, band, injection port, filter, and marble. These jars are specifically designed for mushroom cultivation and are perfect for those who want to create their own mushroom culture. The jars are made from high-quality materials and are designed to be durable and long-lasting. They are easy to use and can be used for a variety of mushroom species. These jars are a great investment for anyone who wants to start growing their own mushrooms at home.