The SPT-10 PAD, measuring 21"x21", is a compact air filter pad from Koch Filter Corp, packaged in sets of 25. This filter is designed for high-efficiency air filtration, effectively capturing dust and other airborne particles. Its size makes it ideal for smaller HVAC systems or specific applications where space is limited. Constructed from high-quality materials, the SPT-10 ensures durability and long-lasting performance. This product complies with industry standards, providing reliable air filtration solutions for both commercial and residential users.