Tire Pressure Monitoring System (TPMS)

I have the TST flow thru system. The batteries need to be replaced at least every year. TST will send you new O-rings for free with a phone call. I never get leaks. The monitor lasts for a week on battery. I plug it into the cig charger in the truck for a few hours while driving to charge it then unplug it and it runs on batteries. I turn it on a few min before driving away and the info is on the monitor. My only complaint is that even thou it is a flow thru system it takes awhile to air up if needed so I take off the sensors to add air. Also if you have a long RV or 5th wheel, my 5th wheel is triple axel, you may need a repeater to send the signal from the tire sensors to the monitor. About an extra $50 bucks.