Specification. Overlockserger has 234 thread and rolled hem capability. Automatic thread trimmer and tension release when the pressure foot is raised. Over edge cutting width dial adjustment. Quick release lever for removing the presser foot and other options. Pre-threaded and swing door design allows for easy access. Offers a differential feed for difficult or stretchy fabrics. Built-in light motor and foot pedal and accessory compartment. Maximum sewing speed 1300 SPM. Stitch length 1-5 mm - Differential ratio 07-20. Roll hem plate built-in. Catch tray and color coded threading diagram