The difference between steel 304 and 316 is that 316 is made of stainless steel is therefore harder and more durable. It lasts longer when you use water that is very acidic, water that contains a lot of salts, for example. sea salt or heavy metals and other pollution. It is also more difficult for bacteria and viruses to adhere to the surface of stainless steel. The 304 version works great if used for water that is not too acidic or contaminated. Zoria at Life of Detox has been using her 304 herself for several years without any problems.