Purchased a tire pressure monitoring system and found they were not seating properly on my inner dual wheels. Would lose all pressure within a few days. Luckily we were parked at the time. Just bought tires and the dealer-installed extension had Schrader valve pins that protruded a little past the edge of the tube, preventing the TPMS from landing. Bought these replacement parts and they worked great. A wrench will help tighten them.