if (document.images) {
	

	var tab = new Image(),
	
	/***rollovers***/
		push_to_connect_on = new Image(),
		push_to_connect_off = new Image(),
		accessories_on = new Image(),
		accessories_off = new Image(),
		brochure_on = new Image(),
		brochure_off = new Image(),
		threaded_port_on = new Image(),
		threaded_port_off = new Image(),
		
		/***selector chart***/
		background_selector = new Image();
		
	/***nav***/
	tab.src = "images/navigation/tab_hover.jpg";
	/***rollovers***/
	push_to_connect_on.src = "images/push_to_connect_hover.jpg";
	push_to_connect_off.src = "images/push_to_connect.jpg";
  
	threaded_port_on.src = "images/threaded_port_hover.jpg";
	threaded_port_off.src = "images/threaded_port.jpg";
	
	accessories_on.src = "images/accessories_hover.jpg";
	accessories_off.src = "images/accessories.jpg";
  
	brochure_on.src = "images/brochure_hover.png";
	brochure_off.src = "images/brochure.png";
	
	/***selector chart***/
	background_selector.src = "images/selection_chart/background_selector.jpg";
   
}
 
function button_on(imgId) {
	var butOn;
	if (document.images) {
		butOn = eval(imgId + "_on").src;
		document.getElementById(imgId).src = butOn;
	}
}

function button_off(imgId) {
	var butOff;
	if (document.images) {
		butOff = eval(imgId + "_off").src;
		document.getElementById(imgId).src = butOff;
	}
}
//End button rollover



function matchColumnHeight() {

	var columnHeightLeft = document.getElementById('main').offsetHeight,
		columnHeightRight = document.getElementById('sidebar').offsetHeight;
	if (columnHeightRight >= columnHeightLeft) {  
		document.getElementById('main').style.height = (columnHeightRight - 27) + 'px';  
		document.getElementById('sidebar').style.height = (columnHeightRight - 27) + 'px';
	} else {  
		document.getElementById('main').style.height = (columnHeightLeft - 27) + 'px';
		document.getElementById('sidebar').style.height = (columnHeightLeft - 27) + 'px'; 
	}
}