"Jiffy 7" Pellet - 1 pellet Compressed peat that expands when water is added. Used for seed starting and cuttings.Jiffy pellets expand after you place them in water or nutrient solutions and are held together with a thin netting material. Used for seedlings and cuttings. Watch out though, they are made from peat moss and your pH will lower. Not good in hydroponic systems because of that very reason. Although, I have heard of hydro people using them to counter alkaline water and were very happy. Please order in increments of 12 or 25.