... seam,decorative seam etc BSL-3800 Series Single/double needle chainstitch sewing machine Feature:1.BSL-3800 is suitalbe for jeans side seam,bedding ... . BSL-3810 1 needle, chainstitch sewing machineBSL-3820 Tendem 2 needle, two chainstitich sewing machineBSL-3830 Parallet 3 needle,.three chainstitch sewing machineparallet 2-needle, needle gauge have 3 ...