The Block-Centered Flow (BCF6) package is one of several packages in MODFLOW that can be used to simulate flow in the saturated zone. The pane for this package is on the MODFLOW Packages and Programs dialog box under Flow Packages. The BCF package input file can not include comments so any comments entered here will be retained in the ModelMuse file but not exported.
When the Block-Centered Flow (BCF6) package is selected, three new data sets may be created: Confined_Storage_Coefficient, Transmissivity, and Vertical_Conductance. All three have default formulas that set their values automatically based on the model geometry along with Specific_Storage, Kx, Kz, and Confining_Bed_Kz. Thus, it usually makes sense to set the values of those other data sets rather than to set Confined_Storage_Coefficient, Transmissivity, or Vertical_Conductance directly.