Option Explicit
Dim colComboboxes As Collection
Private Sub UserForm_Initialize()
Set colComboboxes = New Collection
Dim clsCmb As clsCombobox
Dim cmbX As MSForms.ComboBox
For Each cmbX In Me.Controls
Set clsCmb = New clsCombobox
With cmbX
Call .AddItem("A")
Call .AddItem("B")
Call .AddItem("C")
End With
Set clsCmb.cmb = cmbX
Call colComboboxes.Add(clsCmb)
Next cmbX
End Sub