The chainstitch straight buttonhole machine offers unsurpassed speed and quality in the production of straight buttonholes on all types of garments and material. The chainstitch buttonhole provides increased production with no bobbin changes. The elasticity of the chainstitch also provides the flexibility needed for many fabrics such as knitwear. The high sewing speed of the chainstitch straight buttonhole machine and the short sewing cycle increase productivity and the single pedal electronic start reduces operator fatigue. The S-4000 BH chainstitch straight buttonhole machine can be programmed to sew single or double cycle sew. Changes to the length of the buttonhole are made by a single screw adjustment located on the machine bed.