Singer 27 repair/ replacement parts.  Thread tension assembly.  Includes two tension disks #2102, thread tension stud #413D, tension regulating thumb nut #1560B, tension releaser #8237, tension spring #8238, thread take up spring #8244, spring regulator plate #8245 and regulator adjusting screw #233b.  Price includes shipping to lower 48, return for refund if fails on your Singer 27.