Full Circle Adjustable Sprayer (Bag of 10) has 8 streams of water allowing for the option of changing the flow rate to each individual plant, from a low drip, to a gentle stream, with a diameter of about 3'. Twisting the dial on the dripper towards the "+" or the " -" signs will allow you to adjust the flow between 0 gph and 10 gph. Best used at 25 psi. Excellent for shrub plantings, ground covers, flowers beds, trees, and containers. Barbed drippers can be inserted directly into your main line or used in the end of 1/4" tubing.