Rodless air cylinders propel an internal piston coupled to an external carriage or shuttle along the axis of a housing. Rodless air cylinders are compact and precisely locate start and stop points. Mechanically jointed rodless air cylinders have a rigid, fastened connection between the internal piston and external carriage which passes through the cylinder's slotted housing. Magnetically coupled rodless air cylinders have a strong magnetic field joining the internal piston and external carriage, leaving the housing with a continuous surface. Mounting hardware for rodless air cylinders enhance the mounting possibilities and expand use of these air cylinders.