Rosin parchment paper is used to gather any expelled rosin that comes out of the rosin bags when being pressed in your rosin press. The parchment paper is wrapped around the rosin bags and helps keep the oil contained and your machine clean. Once you have finished pressing your flower, trim, or dry sift, you will open the parchment paper, remove the pressed rosin bag and scape up any oil from the parchment paper for packaging or storing.