The item for sale is 4 Ounces of Magnesium Sulfate Anhydrous (MgSO4); also known as Magnesium Sulphate or Epsom Salts. Magnesium Sulfate Anhydrous is an inorganic, hygroscopic salt commonly used as a drying agent. For Magnesium Sulfate Heptahydrate, check out our other listing. STURDY PLASTIC BOTTLE: Our bottles are made of durable Polypropylene Plastic, which is a natural, translucent, lightweight, durable, and chemically resistant copolymer. The screw-top is completely leakproof. The bottles' round shape makes them a perfect addition to any shelf or travel kit. Every bottle we ship is sealed in plastic with the screw-top shrink-wrapped. HUNDREDS OF USES INCLUDING: Bath Salt Ingredient / Laxative / Brewing Salt / Fertilizer / Stony Coral Nutrient / Dessicant. SHIPS FAST FROM CALIFORNIA, USA: We ship three times a day, seven days a week. This item will be in the mail the same day you place your order. By itself, this item will ship in a padded bubble-mailer (2-5 day transit time). Combined orders exceeding 13 ounces will be upgraded to a flat-rate box (1-3 day transit time) at no additional charge. Please make sure your stated shipping address is correct, complete, and unambiguous. Applicable products are packaged and shipped in accordance with carrier regulations for ORM-D classification.