The ComboBox can pick up the descriptions along the item numbers. That
will make it easier to get the description for a given item number.
The user doesn't have to see it. Set the ComboBox's ColumnCount to 2
and the 2nd column's width to 0, e.g. ColumnWidths = 30 pts; 0 pts. I
assume you have a CommandButton the user clicks to indicate having
selected an Item Number and quantity. Assuming this, something like
the following code should work.

Private Sub CommandButton1_Click()
Dim iRow As Integer
iRow = 1 + Sheets("Order").Range("A65536").End(xlUp).Row
Sheets("Order").Cells(iRow, 1) = ComboBox1.List(ComboBox1.ListIndex,
0)
Sheets("Order").Cells(iRow, 2) = CInt(TextBox1.Value)
Sheets("Order").Cells(iRow, 3) = ComboBox1.List(ComboBox1.ListIndex,
1)
End Sub

Private Sub UserForm_Activate()
Dim iCt As Integer
Dim r As Range
iCt = Sheets("Items").Range("M1")
Set r = Sheets("Items").Range("A3:B" & iCt + 2)
ComboBox1.RowSource = r.Worksheet.Name & "!" & r.Address
End Sub

Hth,
Merjet