A low-flow faucet aerators can reduce your home water consumption as much as 50%.
To install it, simply unscrew your current aerator (by hand, or if it’s tight, use vise-grips or channel-lock pliers). Feel inside the faucet with your finger to make sure the old o-ring isn’t stuck there. Screw on the new aerator by hand. If it leaks a bit, use the vise-grips to tighten it a bit more, or put some plumbing/flux tape over the threads and retighten again.