Check the listing for details. Masterblend Fertilizer Hydroponics 4-18-38. Condition: New. Listed at 10.50 USD. Each Kit Includes: Packet (A) contains 40 grams Masterblend International Water Soluble Fertilizer 4-18-38 Packet (B) contains 20 grams Magnesium Sulfate Packet (C) contains 40 grams Microprill (All macro and micro nutrients included.) Note: To ensure best growing results mix: 2 parts Packet (A) 1 part Packet (B) 2 parts Packet (C) ** (Each packet above typically contains up to 5% more than the labeled amount listed above.) ** Easy to mix with water. Avoid the Premix formulations that might result in precipitating into non-soluble gypsum that plants cannot absorb (nutrient lockout). To get the best results and avoid Nutrient Lockout (follow the 2 easy steps below): Step #1. Thoroughly mix Packets (A) and (B) together with warm water. Step #2 . Thoroughly mix Packet (C) with the mixture from Step #1. Each kit makes from 20 up to 35 gallons. FREE SHIPPING !!! USPS Ground AdvantagePackage Tracking included