Such an important topic! The biggest difference between the molecular sieves is the pore size, which controls what molecules will be adsorbed, and which will be excluded and allowed to pass through the adsorption unit. Our article “…What’s the Difference?” (https://hengyeinc.com/3a-4a-5a-13x-whats-the-difference/) , found in the “Articles” section can further explain the differences between the different types of molecular sieve.