function set_rib_qty()
{
  calc_f = document.frmCalc;
  order_f = document.frmOrder;

  if (calc_f.belts.value == "" || calc_f.ribs.value == "")
  {
    alert("Need both belts and ribs.");
  }
  else
  {
    order_f.qty1.value = calc_f.belts.value * calc_f.ribs.value;
    order_f.txtComment.value = calc_f.belts.value + "X" + calc_f.ribs.value;
  }
}

function J1()
{
  document.write("<form name=frmCalc>");
  document.write("<p style='font-family: verdana, arial; font-size: 1em; font-weight: bold; color: black;' align=center>Enter No. of Belts <input type=text name=belts size=4>");
  document.write("&nbsp; ");
  document.write("No. of Ribs <input type=text name=ribs size=4>");
  document.write(" ");
  document.write("<input type=button value='Calculate' onclick='set_rib_qty();'></p>");
  document.write("<p style='font-family: verdana, arial; font-size: 0.8em; font-weight: normal; color: black;' align=center>*** Remember to click 'Change to Cart' or 'Change & Checkout' after 'calculate'.</p>");
  document.write("</form>");
}