A type of 2 need off the arm double chain stitch machine sultable for joining tubular fabrics; Fit for sewing heavy and medium-heavy material a well as quality shirt, etc. and able to process light weight products in beautiful and soft thread with no puckering; Adopting easy adjustable independently-regulated looper mechanism to prevent from skip stitch and fitted with effective holder; also, the work efficiency being increased by improving the needle gauge; Applicable to joining process on tubular fabrics like varied garment, jeans and shirt, etc.