The higherbro Oxygen O2 Sensor is designed to fit a variety of Toyota Tundra and Sequoia models, including 4.0L, 4.6L, 4.7L, and 5.7L engines. This package includes 4 oxygen sensors, with 2 upstream and 2 downstream sensors for comprehensive coverage. The sensors are made of high-quality stainless steel or aluminum, ensuring durability and longevity. They have a measuring range of 0 to 20% oxygen and operate on 12 volts of direct current. The output type is analog, and the sensors come with a one-year quality guarantee. Before purchasing, please verify that your vehicle is compatible by checking the 'Select Your Vehicle' feature at the top of the listing. Note that the engine and notes in particular are important to consider.