Now let's look at Simporters. So SIM Porters, also known as co transporters, are basically the same exact type of transmembrane protein, except they move in the same direction. So simporters use the spontaneous flow of one molecular ion to move a different molecular ion in the same direction against its electrochemical gradient. And so to visualize that, let's take a look at this diagram. So let's say we have our membrane, this is our Simporter, the outside, the inside of the cell. So now what we have is a reverse of these orange concentrations.