And because we have three of these boundaries between the pairs in any given trimer, we see that we have three of these active sites in any trimer. And because we have two triumphs, that implies we must have six active sites. So we see that the quotinary structure of the ATCAs actually consists of six individual active sites. And that means if all those active sites are occupied at some given moment in time, six of these reactions are taking place at the same exact moment in time. So this is where poly so this is let's suppose the poly molecule, it binds onto this location, the first active side, this location, the second active side, and the third active side as well. And of course, if we flip it this way, we're going to see the other catalytic trimmer and it also contains three of these active sites.