An *extendible* screw. If you inspect the drawing, you'll see that the windings are clones of one, original winding next to the head. By adding or deleting clones you can make the screw longer or shorter.
可伸縮螺絲
clones、metal、screw、tool
克隆、金屬、擰、工具
資料來源：openclipart ( https://openclipart.org/ )