ORO-TEK tire-pressure-monitoring sensors are a drop-in replacement for OEM TPMS sensors, and will link to your vehicle’s TPMS system in the exact same manner as the original units. No proprietary tools are required as are with competing brands, simply follow your same factory relearn procedures as you would with your original OEM sensors. The two-piece sensor/stem design allows for easy maintenance as the stem can be replaced independently of the electronics. Because they're adjustable for angle, they'll install in virtually all wheels, factory or aftermarket. To ensure proper operation, 4 sensors (one per wheel) are required.