This replacement air filter from HDX is designed for use with AprilAire and
Space-Guard systems. With a size of 20 inches by 25 inches by 4 inches, it
offers a MERV 11 rating and a filter life of 12 months. The filter is frameless
and comes in a white color, with a model number of HDX-AXP-213-2.
It's a great choice for those looking to improve their indoor air quality and
keep their heating, cooling, and air systems running smoothly. The filter is
sold as a single unit, and is perfect for use in homes and other living spaces.