Our sintered discs are the absolute highest quality available. Proudly overbuilt and meticulously manufactured right here in Oregon USA, our discs are the only ones that are triple welded and GUARANTEED to not have any media bypassing your filter EVER. Also our high flow support plate gives a 20% faster flow rate for faster run times! Available in 1 thru 5 micron, and 3", 4", 6", or 8" diameter. Other sizes available by request.