The product is a 12-pack of WEB vent filters, measuring 4"x12", designed for electrostatic register filtration. Made in the United States, these filters are specifically designed to improve the air quality in heating, cooling, and air systems. With a 90-day lifespan, these filters are effective in capturing airborne particles and ensuring clean air circulation in homes and buildings. The WEB brand is known for quality and reliability in filtration products, making this a trusted choice for maintaining indoor air quality.