This mission brings supplies such as materials to support 166 experiments in everything from the effects of microgravity to plant biology to needs for the robotic arm (you may recall they had to rig up something when last they repaired it.) The Dragon (SpaceX’s spacecraft for this mission) will connect to the ISS for several weeks before returning to Earth.
In late October the Dragon is expected back with a parachute assisted landing in the Pacific Ocean with several experiment samples and other cargo being returned.
If you are interested in the launch, it is Oct 7th at 8:34pm (at last one I don’t have to set my alarm for!) with a rain date being Oct 8th.