The lightweight, ⅓ ounce sensors feature the latest technology in external sensors on the market and are water resistant. Tire Pressure Monitoring Systems (TPMS) are a proven way to increase fuel efficiency and extend tire life. No tire rebalancing is needed and each sensor comes with a patented anti theft ring to not only prevent theft, but loss from improper installation. The sensors have a unique 20 minute battery saver mode as well as G-Force sensing to wake them up. The monitor comes with its own one hour battery saver mode to insure long life on all components. Includes instruction manual, all batteries, and a silicone protective skin for the monitor.