H-IIB (H2B) is an expendable launch system used to launch H-II Transfer Vehicles (HTV, or Kounotori) towards the International Space Station. H-IIB rockets are liquid-fuelled with solid-fuel strap-on boosters and are launched from the Tanegashima Space Center in Japan. Mitsubishi and JAXA have been primarily responsible for design, manufacture, and operation of H-IIB. H-IIB made its first flight in 2009, and has made a total of five flights through 2015.
H-IIB is able to carry a payload of up to to GTO, compared with the payload of 4,000-6,000 kg for the H-IIA, a predecessor design. Its performance to LEO is sufficient for the HTV. The first H-IIB was launched in September 2009.