content: AN EASY INSTALLATION, JUST FOLLOW THE WRITTEN DIRECTIONS. IT WAS A REPLACEMENT AND I WAS ABLE TO RE-USE MOST OF THE EXISTING LIGHT ANGLE IRON MOUNTING BRACKETS. DOOR SENSORS WERE EASY TO INSTALL AND LINE UP. AFTER INSTALLATION, IT WAS REAL SIMPLE TO MAKE ALL THE FINAL ADJUSTMENT.MY OLD OPENER WAS A CHAIN DRIVEN AND VERY NOISY. I AM VERY PLEASED WITH THE PERFORMANCE AND IMPRESSED WITH THE QUITE OPERATION OF A SCREW TYPE.