Ensures proportion of fertilizer or supplement to water remains constant from the beginning of the cycle until tank is depleted. An adjustable cap with four basic settings controls the amount of fertilizer/supplement mixed with water. Easy to install and use. Can be connected in a variety of ways. Can easily be relocated to feed multiple areas. Most often attached to exterior water faucet (hose bib) with anti-siphon protection. Can be connected to an existing sprinkler or drip irrigation system after any valve as long as the unit is only under pressure while operating. Great when you want to separately address certain types of plants that require special fertilizers or supplements. Made of polyethylene plastic. Total capacity: 3/4 gal.; Fertilizer capacity: 5 lb. Capacity is approximate. Max pressure: 50 PSI (3.45 bars); can only be installed in on/off pressure applications where the system is only under pressure when it is in use. Made in the USA.