The only recommendation I would make to improve the product is to check the measurements of the filter. I found the replacement filter to be a tight fit which required me to squeeze the top to fit the opening.
Nobody stocks a filter of the dimensions I needed. The hack that installed this HVAC in our house ( was here when we bought our home) had cut a 1 3/4 inch opening for a filter. Stock one inch I had to jury rig to keep in place. Finally found these, and with a little modification to the metal work, viola, a filter that fits as it should.
My unit was mislabeled by the installer so the filter I bought based on that misinformation didn't fit. The actual dimensions were out of the ordinary (whoever heard of a 13x21.5 filter). It arrived in a few days , fit perfectly no hassle! Too easy.