I hesitated to buy this unit because of the low price, thinking it's not worth it. I only needed one but opted for a set of four. I was pleasantly surprised when I received the sensor. I removed the wheel from the car, snapped the bead, removed the old rod and sensor, put in a new rod and sensor. Inflated the tire with air, put it back on the car. I went through the GM TPMS learning sequence using the dashboard display. Upon completion, all of my gauges showed the correct pressure, including the new one. I was very satisfied and it only took about 20 pieces to complete the exchange, no more TPMS service message and no trip to the mechanic. Thank you!