Porter Cable Roofing Air Nailers are convenient and durable tools. These nailers feature two different modes of firing. One mode can fire nails one at a time every time you pull the trigger, making for a safe and friendly work environment. The other mode is good if you need to drive nails quickly, it works by holding the trigger the whole time and every time you contact the work surface it fires. To add to the convenience they also use the most common type of roofing nails, 15 deg. wire collated roofing nails.