Why Varchar columns use level number 49

Why Varchar columns use level number 49 Recently I created a new table and had the requirement to create one column with varchar data.  In our project, we clone the existing DCLGEN, as our test regions are on mainframe express and it does not support the creation of DCLGEN. So while writing the DCLGEN, I noticed that a level number 49 is mandatory for declaring the Varchar columns. I really did not get the logic why the varchar columns must be declared on  level number 49, if any of you can throw some light, it would be great “; ; ; ;