function getcom(URL){

var left = (screen.width / 2) - (400 / 2);
var top = (screen.height / 2) - (600 / 2) - 12;

window.open(URL,"Comments","toolbar=0,scrollbars=1,location=0,statusbar=1,menubar=0,resizable=0,width=400,height=600,left="+left+",top="+top+"");
}