You get 2 boxes of high quality Pilot BeGreen 0.3mm lead refills (1 box of HB and 1 box of B). Small 0.3mm leads need to be strong to resist breaking. These made in Japan leads are very strong. BeGreen means they use recycled plastic in the box.
HB is your standard medium hardness. B is slightly softer, they make a darker line and do not catch the paper fibres as easily as the harder leads.