1、Rotating sewing machine hook+flat gear, owns simple structure, stable quality and high efficiency. 2、Multifunctional rotating hook for household sewing machine, a good helper for bobbin. 3、Indispensable accessories for sewing machines, fine workmanship for long‑term use. 4、Manufactured from premium iron material, can stand up to a lot of wear and tear, practical and durable. 5、Wonderful replacement for the previous old or broken one, easy to install. 1 x Sewing Machine Hook Item Type: Sewing Machine HookMaterial: IronColor: Black+SilverModel: 153021Diameter: Approx. 5cm/ 2.0inApplication: Suitable for Singer Household Sewing MachineOperation: Most of these sewing machines use rotating hook, which hook the thread loop with its tip while expanding the thread loop and guiding the thread loop around the bobbin to form a lock stitch.