Just thinking about buying a TPMS Relearn Tool, off eBay. Has anyone had experience with any of these? I have heard that there are real ones and cheap knock offs. How to tell the difference, or are they equally as good? I see a lot of the eBay listings say “Unbranded”. Is this bad? Any help would be appreciated. Most say for 315 and 433 MHz sensors. Does anyone know what the 2nd generation TPMS specs. are.