Selected Listbox Values In SQL Statement

I have seen some information on this but have not understood fully the answers.  I am fairly new to this and have spent the afternoon trying to work on this and although I have leant some really cool things I am no nearer.  How do I get selected values from a LIstbox into a SQL statement using the IN command  
First I loop through a List box control to get the multi selected values: Dim li As ListItemFor Each li In lbPClass.Items  If li.Selected = True Then    strPC += li.Value & ", "  End IfNextLabel5.Text = strPC The result in the lable looks something like: 100, 101, 102 , I get rid of the trailing blank and commar with:Label6.Text = Left(Label5.Text, Trim(Len(Label5.Text) - 2)) I have created a parameter called @PROPCLASS that will use the values from the selected values in the listbox in a SQL query using an IN statement: Cmd.Parameters.Add(New OleDbParameter("@PROPCLASS", Label6.Text)) strSQL = "SELECT * FROM web_transfer WHERE ( PROP_CLASS IN (@PROPCLASS)) AND (ACRES >= @lowSize)AND (ACRES < @HighSize)  AND (YEAR = @lowYear)AND (SALE_PRICE > @lowPrice) AND (SALE_PRICE < @highPrice) " 
It is really the first bit of the WHERE clause I am interested in.  The sql statement works if I either type in the actual values IN( 100, 101,102) or if I select only one value in the list box.  If I select two then the sql statement does not work. 

My question is: How do I get the values selected in the List box into my SQL statement   Thank you in advance, s