SummaryIt is a small part to easy the assemble of y-carriage and vertical frame by keeping the washers in place. Part is removed on assembly.InstructionsKeeping washers in place is the only thing done by this part. You insert it instead of the frame and the bottom shape will help it to be pushed out when inserting the frame. Please note you will need to turn the part to remove it, as it will push against the smooth rod that it is on top. This part is designed for 10mm threaded rods, which is the latest version of Prusa i3 y-carriage.