Scientific Inhalations Filters are made in the USA by professional glass artisans using high-quality glass and ground joints. Filters can be filled with Organic Cotton or Virgin Coconut Carbon. Help your body experience the benefits of a cooler, cleaner delivery method and still retain the potency and flavor of your medicine. Scientific Inhalations Original Filter Adapter is handmade with high quality (Schott or Simex) glass in California. This filter adapter includes 18mm to 18mm joints.