The 3A model has a larger capacity which is 500 gallon but I’ve heard that they already stop manufacturing these models. The difference between 3A and 3B is that since 3A has a larger capacity, it can handle large flow, meaning you can easily fill a cup of water faster than 3B. Both filters have the same expiration and must be replaced within six months to ensure you have a healthy drinking water all the time. It is also recommended to always have a spare filter on stock for a quick and easy replacement if needed.

Installing these filters are very easy and you don’t need any tool or be a professional to do it. You can remove it simply by twisting, and then pull the old filter. Installing the new filter is just as easy; insert the new filter and twist to lock it in place.