VBA / Formatting Textbox To Number With 3 Decimal Places

I need to have textBox2. formatted to a number with 3 decimal places.

The code below is executed from the command button.

Code:
Private Sub CommandButton1_Click()
If IsNumeric(Me.TextBox1.Value) Then
Me.TextBox2.Value = Me.TextBox1.Value / 25.4
End If
End Sub

I found the code below but I cannot seem to figure it out

Code:
Private Sub TextBox2_Change()
TextBox2.Text = Format(Number, "0.000")
End Sub