Water filter manufacturers turned their sites to materials already being used in
high quality food products and found 304 grade stainless steel was leading the way in quality and durability for many highly success consumer products. It was from this point forward leading Japanese manufacturers began using high quality food grade stainless steel for the manufacturing of their water filters and drinking utensils. When shopping for a stainless steel water filter ensure they are made for 304 food grade stainless steel.