I have
TST, Tire Pressure Monitoring Systems myself. The 507 System is what I have, with replaceable batteries. I have 2 ten tire systems for our two motorhomes and two toads. Our Sport Trac has it's own additional tire monitor used with the kit's monitor for use when unhooked from the motorhome. The 2011 Miata, I'm setting up now, has an OEM in-tire system that is not compatible with the TST monitor. I've added the TST sensors "at the valve stem" so we can monitor the Miata's tire pressures and temperatures also from the motorhome without an additional monitor to clutter the of the Miata dash. I also have a repeater mounted in the rear closet of the motorhome, as I did with our previous Pressure Pro System. I have gotten about 12-18 month battery life and have bought replacements from Amazon for around $16 for 20, 1632 Energizer Lithium Ion batteries. My original Pressure Pro system was replaced with the TST system, since those sensors had to be replaced when the batteries failed at 5-7 years at a cost that seemed to go up each time ordered. The sensor replacements started at at about $25 each in 2006 and were around $40 each in 2015.
