In the Layer Control, selecting the Masks layer, then RMC to show options as shown in Figure 1. These options are described below.
Anchor Figure 1 Figure 1 
Figure 1 Layer's RMC options
Properties
Once After selecting the Properties option, the Mask Properties form appears as shown in Figure 2. From this form, the user can set a new name for Layer Name. Check the box for Layer Visible will allow the grid mask display to be toggled in the 2DH View. Check the box of Show in Legend will allow the legend of the grid mask to be displayed in the Legend in the 2DH View. Checking this box is only applied when the Layer Visible option is checked. Settings for styles and colors of masks are also applied from this form.
Anchor Figure 2 Figure 2
Figure 2 Mask Properties
Edit
Selecting this option, the 2DH View Option form will be displayed as Figure 3. From this form, the user can change the current layer (Masks) to another layer by selecting from the drop-down list in the Primary Group and Parameter.
Anchor Figure 3 Figure 3
Figure 3 2DH View Options form
Edit Cell Blocking Mask
Edit This option edits cells that have masks. When this option is selected, Vertical Vertical Cell Face Blocking form appears as shown in Figure 4.
On the Vertical Cell Face Blocking form as shown in Figure 4, it shows all the grid cells of the domain, which has masks of the domain on the List of Cells frame. I, J, and L indices of the cell are shown in the Cell Indices frame. Initial conditions of the cell, including bottom elevation, water depth, water surface elevation, are shown in the Initial Conditions frame, these fields are not editable. The user can edit the cell's mask by changing the mask's properties on the Current Cell frame.