... 3800 Series Single/double needle chainstitich sewing machine widely used for side seam,decorative seam etc BSL-3800 Series Single/double needle chainstitch sewing machine Feature ... :1.BSL-3800 is suitalbe for jeans side seam,bedding, ... machineparallet 2-needle, needle gauge have 3.2, 4, 4.8, 5.6, 6.4, 8, 9.5, 12.7mm options.