From the manufacturer:
This versatile 33-piece calligraphy pen set features interchangeable nibs, inks and pens. It includes four pens, five nibs (extra-fine, fine, medium, broad and extra-broad), 20 ink cartridges (five each black and blue and two each yellow, orange, pink, green and brown), a pump, a practice paper pad and a step-by-step instruction booklet in a handsome storage tin.