The Hart Universal Standard Dust Bag is a high-quality vacuum cleaner bag designed to fit 4-9 gallon bags. It is compatible with a wide range of universal vacuum models, making it easy to use with different types of vacuators. The pack includes 1 bag, ensuring that you have an extra on hand for when you need it. The Hart brand is known for producing reliable and durable cleaning supplies, making this dust bag a trustworthy option for maintaining clean and healthy air in your home.