The only "save" I can remember in 6 years with my TST507 was after being evacuated from a state park in Panama City, FL due to a hurricane. I moved 30 miles north and waited it out. The night before the return to Panama City I checked all 4 trailer tires for pressure and reinstalled the sensors (non flow through). The next morning while leaving my site the alarm went off for my right front tire. I had moved about 50'. It seems I didn't install the sensor tight enough and it leaked down enough overnight to trip the TST507 alarm. How far would I have driven before I noticed a shredded tire if the 507 wasn't there? Who knows, but I won't drive anywhere without my TST507.