Progress-M1

ISS Propellant Refueling, Mir Deorbiting Progress is derived from the manned Soyuz spacecraft and is launched on the same vehicle, a Soyuz rocket. The purpose of Progress is to deliver supplies needed to sustain human presence in orbit. Currently it is used as a re-supply spacecraft for the ISS. Progress-M1 is used to resupply space stations. It is a variant of the Progress spacecraft, derived from the Progress-M, but modified to carry more UDMH and N2O4 propellant for refuelling the International Space Station instead of other cargoes such as water.