function roll_over(img_name, img_src)
   {
   document[img_name].src = img_src;
   }
  
function CheckOption()	
{
	var bReturn = true;
	try{
		if (document.getElementById('selColour').value == "0")
		{
			alert('please select a size/length/core');
			bReturn = false;
		}
	}
	catch(Ex){}
		
	try{
		if (document.getElementById('selSize').value == "0")
		{
			alert('please select a size/length/core');
			bReturn = false;
		}
	}
	catch(Ex){}
		
	
	return bReturn;
	
}

function UpdateDelivery(){
	
	var dblAmount = (document.getElementById('selDel').value * 1.15)-document.getElementById('selDel').value;
	var dblGT = document.getElementById('aGT').innerHTML;
	var dblDel = document.getElementById('selDel').value;
	
	//alert(dblGT);
	dblDel = 1 * dblDel;
	dblGT = 1 * dblGT;
	dblGT = dblGT + dblAmount + dblDel;
	//alert(dblGT);
	dblAmount = dblAmount.toFixed(2); 
	document.getElementById('aDelVAT').innerHTML = '£' + dblAmount;
	
	dblGT = dblGT.toFixed(2);
	document.getElementById('aGT').innerHTML = dblGT;
	//alert(dblGT);
	
}