Frame and two sleeves, size 16x25x1.
This worked great, and is especially good for homes with allergies or pets. You can wash the sleeve as often as you like to keep the air clean.
We replaced the HVAC, and the new unit uses a different size filter.
Also including one new disposable filter that was left over of the same size.
See manufacturer's description here:
https://cycleairfilters.com/products/cycle-air-permanent-machine-washable-hvac-furnace-filter-made-with-100-recycled-materials?variant=40881269768246
and here:
https://cycleairfilters.com/products/cycle-air-replacement-filter-sleeve