Andrews was recommended by a friend in the home improvement business. After an exhaustive six year search, I am now able to get rid of that crappy reusable filter that came with the unit that previous owner installed. This is the go to place for all your filter needs. They do walk in retail for us do it yourself homeowner types. Their knowledge is priceless. Just by looking at my old filter and measuring, they knew what I needed and had it in stock. Just an all around awesome experience. Super friendly and great sense of humour. Andrews does more than sell filters for just about every oddball size HVAC unit, they solve problems and solve them without drama. And Damn nice people to boot. If your curious, I’m a 19×21. Don’t even think about finding that size at the big box retailers.