The higherbro Oxygen Sensor is designed for compatibility with a range of 2004-2005 models including Chevrolet Impala, Monte Carlo, Buick Lesabre, Park Avenue, Pontiac Bonneville, and Grand Prix, all with 3.8L engines. This 2-piece set includes both upstream and downstream sensors, ensuring comprehensive coverage for your vehicle's emission system. The sensors are made of durable stainless steel and aluminum oxide, providing long-lasting performance and resistance to corrosion. They offer an analog electrical signal output type and a maximum supply voltage of 5 volts. Each purchase is backed by a one-year quality guarantee, giving you peace of mind in your purchase. Before buying, please verify your vehicle's compatibility by checking the 'Select Your Vehicle' option at the top of the product link, taking into account the make, model, year, engine, and any additional notes.