Grow Microgreens With Ease! Self Watering Adapter Caps, You will receive a Set of 2 This adapter will turn any standard size soda bottle or glass canning jar into an effortless watering system for your Microgreens. This adapter has been designed for both a standard soda bottle OR a regular mouth glass canning jar. Will fit a quart (32) or pint (16) jar. Each adapter will fit both. Regular mouth jar, turn adapter over and use reverse side for pop bottle. *Only fits regular mouth size jars. Will not fit WIDE MOUTH style. Jar or bottle not included. Fill jar/bottle with water and choice of water or nutrient, add adapter, turn upside down and place in glass dish. You are ready to add your clay growing stones (leca), distribute minigreen seeds, place in a dark area while seeds germinate, then move into a lit area - Grow & Enjoy! The material used to cut end caps is PVC vinyl board and will NOT degrade when submerged in water, will last for years. Dishwasher safe for cleaning. Each Adapter measures approximately 5" in diameter x 5/8" thick