Bought an 8x13x1 custom filter. They arrived quickly, well constructed and matched the specified measurements. My only complaint is that for such a small filter which didn't really need any extra support, the 'criss-cross' cardboard pattern across the filter material took up a significant amount of the actual face area - maybe 40-50%. I cut it away to ensure maximum filtering and minimal resistence, and that was a slight inconvenience. Would be nice if a more 'open' construction could be used for small filters.