It is easy to use and install. Has the potential to monitor up to 22 tires simultaneously on your motorhome and towed vehicle, or your truck and trailer. When an abnormality in tire pressure occurs, the TireMinder® TPMS monitor will display and identify the exact tire pressure from 0 to 145 PSI on the easy-to-read digital display (accuracy is within 2.7%). Blow-out alarm gives audible and visual alerts for loss of tire pressure and/or tire temperature over 167º F. The TireMinder® monitor may be mounted anywhere in your vehicle. Monitor operates up to 30 days before needing to be plugged into a cigarette lighter charger. Transmitters may be mounted at any tire location and functions 9 to 12 months on replaceable CR1632 lithium batteries (an extra is included - 8 pcs total). No need to replace the entire transmitter as with other systems. TPMS transmitters have a range of approximately 60'. This distance may be increased by extreme cold, battery condition or interference from other electronics in the vicinity. To increase signal strength (up to 120'), there is an included "Booster." **Bonus** Free battery replacement though 2018!!** - Send TireMinder your battery for safe environmental disposal and they will send you free replacement batteries though 2018!