The Singer 212U (for example, the 212U141A variant) is a high-speed, industrial double-needle lockstitch sewing machine made in Japan (and also in the UK, USA, and Germany in related 212 series) that excels at consistent twin-needle stitching for lightweight to medium fabrics. It combines bottom-feed and needle-bar feed mechanisms for superior fabric control, supports interchangeable twin-needle gauges (commonly 1/4″ or 3/16″ but customizable), and runs at speeds up to 4,000 stitches per minute,
