The Heritage Farms Purple Martin House System Top Perch is the perfect way to give your purple martins a break. This easy-to-install accessory attaches to your existing Heritage Farms Quad Pod Purple Martin Pole System (not included) and will provide your purple martins with six 20.75 long perches on which to rest. Simply position the perches into their respective positions place the perch base assembly over the existing pole top cap and attach the assembly with the included self-tapping screws. Enjoy the beautiful sights and sounds of your perching purple martin colony. . Note: This description refers only to the Heritage Farms Purple Martin House System Top Perch. The pole and home shown are not included. A #3 Phillips head screwdriver is also required for installation. Dimensions: 46.5 dia. (perch to perch) Mounting: screws onto pole Construction: steel