FASCO F1B A11-16 Stapler Auto L/M: Adjustable automatic speed firing capability and a long magazine. Uses easy-to-find Rapid 11 and Senco H series staples that will interchange with manual A11 slap hammers. Speed knob lets you pick the desired speed - from single shot to wicked fast. The double length magazine cuts loading frequency in half. Great for felt paper, house wrap, BIB insulation and screening jobs youll tackle.