How to sew a Double Welt Pocket

The white strip is just a PP strap. (00:58) This is in order not to slide while sewing (sewing gap). When the thickness of the fabric is different, the pressure of the presser foot and the feed dog are not stable. Putting this tape means adding the height, this is very useful. It is used for stitch guide in this case. 1 needle sewing machine : DDL5550N JUKI 1 needle overlock sewing machine : MO3604 JUKI Bar tack and Eyelet stitch sewing machine : LK1900ASS JUKI