Say goodbye to the days of having to unthread your sewing machine in the middle of a project, just to wind a bobbin. Meet the customer-inspired SINGER® Universal Bobbin Winder– a must-have for every busy sewist-on-the-go! This sewing game changer is an external bobbin winder that quickly and easily fills bobbins with thread. It keeps you from having to unthread your sewing machine to fill a bobbin, then re-thread the machine again! With the one-touch auto winding system, bobbins are filled quickly and easily. The auto shut-off feature automatically stops the winding when the bobbin is full. It also includes two spindles for additional bobbin storage. The Universal Bobbin Winder is conveniently housed within a compact and portable case, making it easy to store, use at home, or wind bobbins on-the-go! Whether you need to wind a bobbin that’s low on thread or change your bobbin thread color in a jiffy, the SINGER Universal Bobbin Winder is your go-to bobbin-filling partner! Details:5.7" x 4.13" x 5.32"Auto shut-off feature when bobbin is fullIncludes 2 spindlesUse power cord or 3 AA batteries (not included)Compatible with Class 15 and 15J bobbins