function callback_pop(product, webdomain) {
	var width = 330;
	var height = 550;
	var viewportwidth = 0;
	if (typeof window.innerWidth != 'undefined') {
		viewportwidth = window.innerWidth
	} else if (typeof document.documentElement != 'undefined' && typeof document.documentElement.clientWidth != 'undefined' && document.documentElement.clientWidth != 0) {
		viewportwidth = document.documentElement.clientWidth
	} else {
		viewportwidth = document.getElementsByTagName('body')[0].clientWidth
	}
	var left = (viewportwidth - 925) / 2 + (925 - width);
	if (left > viewportwidth - width) {
		left = viewportwidth - width - 20;
	}
	var win = window.open(webdomain+"callback_pop.php?product="+product, null, "toolbar=no,location=no,resizable=yes,menubar=no,scrollbars=yes,width="+width+",height="+height+",left="+left+",top=100");
}